7th Drug hypersensitivity meeting: part two

Table of contents Poster walk 11: miscellaneous drug hypersensitivity 2 (P92–P94, P96–P101) P92 16 years of experience with proton pump inhibitors (PPIs) Javier Dionicio Elera, Cosmin Boteanu, Maria Aranzazu Jimenez Blanco, Rosario Gonzalez-Mendiola, Irene Carrasco García, Antonio Alvarez, Jose Julio Laguna Martinez P93 Allergy evaluation of quinolone induced adverse reactions Jaume Martí Garrido, Carla Torán Barona, Carolina Perales Chorda, Ramón López Salgueiro, Miguel Díaz Palacios, Dolores Hernández Fernández De Rojas P94 Bupropion-induced acute urticaria and angioedema, a case report Emre Ali Acar, Ayse Aktas, Aylin Türel Ermertcan, Peyker Temiz P96 Delayed type hypersensitivity and study of cross-reactivity between proton-pump inhibitors Chien-Yio Lin, Chung-Yee Rosaline Hui, Ya-Ching Chang, Chih-Hsun Yang, Wen-Hung Chung P97 Diagnostic work-up in suspected hypersensitivity to proton-pump inhibitors: looking at cross-reactivity Fabrícia Carolino, Diana Silva, Eunice Dias De Castro, Josefina R. Cernadas P98 Management of infusion-related hypersensitivity reactions to enzyme replacement therapy for lysosomal diseases Luis Felipe Ensina, Carolina Aranda, Ines Camelo Nunes, Alex Lacerda, Ana Maria Martins, Ekaterini Goudouris, Marcia Ribeiro, José Francisco Da Silva Franco, Leandra Queiroz, Dirceu Solé P99 Management of insulin allergy with continuous subcutaneous insulin infusion Ceyda Tunakan Dalgiç, Aytül Zerrin Sin, Fatma Düsünür Günsen, Gökten Bulut, Fatma Ömür Ardeniz, Okan Gülbahar, Emine Nihal Mete Gökmen, Ali Kokuludag P100 Off-label use of icatibant for management of serious angioedema associated with angiotensin inhibitors Ana M. Montoro De Francisco, Talía Mª De Vicente Jiménez, Adriana M. Mendoza Parra, Angella M. Burgos Pimentel, Amelia García Luque P101 Thiocolchicoside anaphylaxis: an unusual suspect? Luis Amaral, Fabricia Carolino, Leonor Carneiro Leão, Eunice Castro, Josefina Cernadas Poster walk 12: betalactam hypersensitivity (P102–P111) P102 A curious delayed reading: a case report of a β-lactam allergy in a child Nicole Pinto, Joana Belo, João Marques, Pedro Carreiro-Martins, Paula Leiria-Pinto P103 Betalactam-induced hypersensitivity: a 10-years’ experience Amel Chaabane, Haifa Ben Romdhane, Nadia Ben Fredj, Zohra Chadly, Naceur A. Boughattas, Karim Aouam P104 Cefazolin hypersensitivity: towards optimized diagnosis Astrid P. Uyttebroek, Chris H. Bridts, Antonino Romano, Didier G. Ebo, Vito Sabato P105 Clavulanic acid allergy: two cases report Anabela Lopes, Joana Cosme, Rita Aguiar, Tatiana Lourenço, Maria-João Paes, Amélia Spínola-Santos, Manuel Pereira-Barbosa P106 Diagnosis of betalactam allergy in an allergy department Cíntia Rito Cruz, Rute Pereira Dos Reis, Elza Tomaz, Ana Paula Pires, Filipe Inácio P107 Diagnostic work-up of 410 patients with suspicion of betalactam antibiotic hypersensitivity Filipe Benito-Garcia, Inês Mota, Magna Correia, Ângela Gaspar, Marta Chambel, Susana Piedade, Mário Morais-Almeida P108 Immediate selective hypersensitivity reactions to clavulanic acid Alla Nakonechna, Yurij Antipkin, Tetiana Umanets, Fernando Pineda, Francisca Arribas, Volodymyr Lapshyn P109 Prevalence and incidence of penicillin hypersensitivity reactions in Colombia Pablo Andrés Miranda, Bautista De La Cruz Hoyos P110 Selective sensitization to amoxicilin and clavulanic acid Jose Julio Laguna Martinez, Aranzazu Jimenez Blanco, Javier Dionicio Elera, Cosmin Boteanu, Rosario Gonzalez-Mendiola, Marta Del Pozo P111 Infliximab-specific T cells are detectable also in treated patients who have not developed anti-drug antibodies Alessandra Vultaggio, Francesca Nencini, Sara Pratesi, Andrea Matucci, Enrico Maggi Poster walk 13: biologicals, local anesthetics, others (P112–P118) P112 A case report of allergic immediate systemic reaction to adalimumab and certolizumab Ceyda Tunakan Dalgiç, Fatma Düsünür Günsen, Gökten Bulut, Fatma Ömür Ardeniz, Okan Gülbahar, Emine Nihal Mete Gökmen, Aytül Zerrin Sin, Ali Kokuludag P113 Allergy to local anesthetics: negative predictive value of skin tests Ivana Cegec, Danica Juricic Nahal, Viktorija Erdeljic Turk, Matea Radacic Aumiler, Ksenija Makar Ausperger, Iva Kraljickovic, Iveta Simic P114 Cutaneous adverse reactions of molecular targeted agents: a retrospective analysis in 150 patients in our department Yukie Yamaguchi, Tomoya Watanabe, Megumi Satoh, Tomohiko Tanegashima, Kayoko Oda, Hidefumi Wada, Michiko Aihara P115 Generalized paralysis induced by local lidocaine injection Jaechun Jason Lee, Jay Chol Choi, Hwa Young Lee P116 Hypersensitivity to local anaesthetics: a 10 year review Rosa-Anita Rodrigues Fernandes, Emília Faria, Joana Pita, Nuno Sousa, Carmelita Ribeiro, Isabel Carrapatoso, Ana Todo Bom P117 Local anaesthetics: a rare culprit in hypersensitivity reactions Ana Rodolfo, Eunice Dias-Castro, Josefina Cernadas P118 Stevens–Johnson syndrome in clinical practice: a variant of clinical course Marina Voronova Poster walk 14: RCM (P119–P128) P119 13 cases of severe anaphylactic reactions due to radiocontrast media Jaume Martí Garrido, Ramon Lopez Salgueiro, Diana Kury Valle, Verónica Pacheco Coronel, Carolina Perales Chordá, Dolores Hernandez Fernandez De Rojas P120 Anaphylactic shock after administration of iodinated contrast medium during cardiac catheterization Roselle Catherine Yu Madamba, Marta Ferrer, Maria Jose Goikoetxea, Carmen D’Amelio, Amalia Bernad, Olga Vega, Gabriel Gastaminza P121 Anaphylactic shock and cardiac arrest induced by gadolinium-based contrast agents Beatriz Pola Bibián, Marina Lluncor Salazar, Gemma Vilà Nadal, Ana María Fiandor Roman, Javier Dominguez Ortega, Miguel Gonzalez Muñoz, Santiago Quirce Gancedo, Maria Rosario Cabañas Moreno P122 Anaphylaxis to gadobenate and cross-reactivity to other gadolinium-based contrast agents in two patients Kathrin Scherer Hofmeier P123 Anaphylaxis to glatiramer acetate in a patient with multiple sclerosis Fabrícia Carolino, Vladyslava Barzylovych, Josefina R. Cernadas P124 Delayed hypersensitivity reaction to radiocontrast media Fabrícia Carolino, Diana Silva, Leonor Leão, Josefina R. Cernadas P125 Drug reaction with eosinophilia and systemic symptoms induced by iodixanol Gemma Vilà-Nadal, Beatriz Pola, Marina Lluncor, Ana Fiandor, Teresa Bellón, Javier Domínguez, Santiago Quirce P126 Electronic consultation support system for radiocontrast media hypersensitivity changes clinician’s behavior Min-Suk Yang, Sun-Sin Kim, Sae-Hoon Kim, Hye-Ryun Kang, Heung-Woo Park, Sang-Heon Cho, Kyung-Up Min, Yoon-Seok Chang P127 Hypersensitivity reactions to iodinated contrast media: skin testing and follow-up Danica Juricic Nahal, Ivana Cegec, Viktorija Erdeljic Turk, Iva Kraljickovic, Matea Radacic Aumiler, Ksenija Makar Ausperger, Iveta Simic P128 Would iodine allergy exist? Clémence Delahaye, Jenny Flabbee, Julie Waton, Olivia Bauvin, Annick Barbaud Poster walk 15: MPE/type 4 (P129–P137) P129 Delayed hypersensitivity cutaneous reactions: a case/control study from a tunisian database Karim Aouam, Najah Ben Fadhel, Zohra Chadly, Nadia Ben Fredj, Naceur A. Boughattas, Amel Chaabane P130 Delayed hypersensitivity reactions to cephalosporins: a review of seven cases Joana Cosme, Anabela Lopes, Amélia Spínola-Santos, Manuel Pereira-Barbosa P131 Diclofenac induced allergic contact dermatitis: case series of four patients Sandra Jerkovic Gulin, Anca Chiriac P132 Late-onset maculopapular rash to irbesartan Bárbara Kong Cardoso, Elza Tomaz, Regina Viseu, Filipe Inácio P133 Nonimmediate hypersensitivity reactions to betalactams: a retrospective analysis Ana Moreira, Susana Cadinha, Ana Castro Neves, Patricia Barreira, Daniela Malheiro, J. P. Moreira Da Silva P134 Occupational airborne contact dermatitis to omeprazole Ružica Jurakic-Toncic, Suzana Ljubojevic, Petra Turcic P135 Ornidazole-induced fixed drug eruption confirmed by positive patch test on a residual pigmented lesion Liesbeth Gilissen, Sara Huygens, An Goossens P136 Repeated delayed reaction induced by amoxicillin and amoxicillin clavulanate Inmaculada Andreu, Ramon Lopez-Salgueiro, Alicia Martinez Romero, Pau Gomez Cabezas P137 Systemic photosensitivity from fenofibrate in a patient photo-sensitized to ketoprofen Liesbeth Gilissen, An Goossens Poster walk 16: HLA genetics (P138–P146) P138 A copy number variation in ALOX5 and PTGER1 is associated with nonsteroidal anti-inflammatory drugs induced urticaria and/or angioedema Pedro Ayuso Parejo, Maria Del Carmen Plaza-Serón, Inmaculada Doña, Natalia Blanca López, Carlos Flores, Luisa Galindo, Ana Molina, James Richard Perkins, Jose Antonio Cornejo-García, José Augusto García-Agúndez, Elena García-Martín, Paloma Campo, María Gabriela Canto, Miguel Blanca P139 Association of galectin-3 (LGALS3) single nucleotide polymorphisms with non-steroidal anti-inflammatory drugs-induced urticaria/angioedema José Antonio Cornejo-Garcia, Inmaculada Doña, Rosa María Guéant-Rodríguez, Natalia Blanca-López, María Carmen Plaza-Serón, Raquel Jurado-Escobar, Esther Barrionuevo, María Salas, María Luisa Galindo, Gabriela Canto, Miguel Blanca, Jean-Louis Guéant P140 Detection of T cell responses to ticlopidine using peripheral blood mononuclear cells from HLA-A*33:03+ healthy donors Toru Usui, Arun Tailor, Lee Faulkner, John Farrell, Ana Alfirevic, B. Kevin Park, Dean J. Naisbitt P141 Epistasis approaches to identify novel genes potentially involved in NSAIDs hypersensitivity James Richard Perkins, Jose Antonio Cornejo García, Oswaldo Trelles, Inmaculada Doña, Esther Barrionuevo, María Salas, María Auxiliadora Guerrero, Miguel Blanca, Alex Upton P142 Genetic predisposition of cold medicine related SJS/TEN with severe ocular complications Mayumi Ueta, Hiromi Sawai, Chie Sotozono, Katushi Tokunaga, Shigeru Kinoshita P143 HLA-B*13:01 and dapsone induced hypersensitivity in Thai population Chonlaphat Chonlaphat Sukasem, Patompong Satapornpong, Therdpong Tempark, Pawinee Rerknimitr, Kulprapat Pairayayutakul, Jettanong Klaewsongkram P144 HLA-B*15:02 alleles and lamotrigine-induced cutaneous adverse drug reactions in Thai Chonlaphat Sukasem, N. Koomdee, T. Jantararoungtong, S. Santon, A. Puangpetch, U. Intusoma, W. Tassaneeyakul, V. Theeramoke P145 HLA-B*38:01 and HLA-A*24:02 allele frequencies in Spanish patients with lamotrigine-induced SCARs Teresa Bellón, Elena Ramirez, Alberto Manuel Borobia, Hoi Tong, Jose Luis Castañer, Francisco José De Abajo P146 Overrepresentation of a class II HLA haplotype in severe hypersensitivity type I reactions to carboplatin Violeta Régnier Galvao, Rebecca Pavlos, Elizabeth Mckinnon, Kristina Williams, Alicia Beeghly-Fadiel, Alec Redwood, Elizabeth Phillips, Mariana Castells Poster walk 17: in vivo diagnosis + sIgE (P147–P154) P147 Absence of specific Ig-e against beta-lactams 9 months after an allergic reaction to amoxicillin-clavulanic acid Elisa Boni, Marina Russello, Marina Mauro P148 Drug provocation tests in suspected opioid allergy Kok Loong Ue, Krzysztof Rutkowski P149 Improvement to the specific IgE cut-off in the assess of β-lactamic allergy Victor Soriano Gomis, Jorge Frances Ferre, Angel Esteban Rodriguez, Vicente Cantó Reig, Javier Fernandez Sanchez P150 Initial false negative specific IgE to gelatin in a patient with gelatin-induced anaphylaxis Christine Breynaert, Erna Van Hoeyveld, Rik Schrijvers P151 Inmediate reactions to beta-lactam antibiotics: pattern of skin test response over the time Jose Julio Laguna Martinez, Rosario Gonzalez Mendiola, Javier Dionicio Elera, Cosmin Boteanu, Aranzazu Jimenez Blanco, Marta Del Pozo, Raquel Fuentes Irigoyen P152 New fluorescent dendrimeric antigens for the evaluation of dendritic cell maturation as a test to detect allergy reactions to amoxicillin Daniel Collado, Yolanda Vida, Francisco Najera, Ezequiel Perez-Inestrosa, Pablo Mesa-Antunez, Cristobalina Mayorga, María José Torres, Miguel Blanca P153 Positive skin test or positive specific IgE to penicillin does not predict penicillin allergy Line K. Tannert, Charlotte G. Mortz, Per Stahl Skov, Carsten Bindslev-Jensen P154 Significance of skin testing and in vitro-analysis of neuromuscular blocking agents in diagnosis of perioperative drug hypersensitivity: evaluation of a negative control population Wolfgang Pfützner, Hannah Dörnbach, Johanna Visse, Michele Rauber, Christian Möbs Poster walk 18: in vitro/ex vivo (P155–P158, P160–P164) P155 Diagnostic value of the lymphocyte toxicity assay (LTA) and the in vitro platelet toxicity assay (IPTA) for β-lactam allergy Abdelbaset A. Elzagallaai, Lindsey Chow, Awatif M. Abuzgaia, Michael J. Rieder P156 Enzyme linked immunospot assay used in the diagnosis of severe cutaneous adverse reactions to antimicrobials Alec Redwood, Jason Trubiano, Rebecca Pavlos, Emily Woolnough, Kaija Stautins, Christina Cheng, Elizabeth Phillips P157 Evaluation of in vitro diagnostic methods for identifying the culprit drugs in drug hypersensitivity Kenichi Kato, Hiroaki Azukizawa, Takaaki Hanafusa, Ichiro Katayama P158 Ex-vivo expanded skin-infiltrating T cells from severe drug eruptions are reactive with causative drugs: a possible novel method for determination of causative drugs Toshiharu Fujiyama, Hideo Hashizume, Takatsune Umayahara, Taisuke Ito, Yoshiki Tokura P160 In vitro release of IL-2, IL-5 and IL-13 in diagnosis of patients with delayed-type nickel hypersensitivity Mira Silar, Mihaela Zidarn, Helena Rupnik, Peter Korosec P161 Single cell analysis of drug responsive T cells; identification of candidate drug reactive T cell receptors in abacavir and carbamazepine hypersensitivity Alec James Redwood, Kaija Strautins, Katie White, Abha Chopra, Katherine Konvinse, Shay Leary, Rebecca Pavlos, Simon Mallal, Elizabeth Phillips P162 Specificity and sensitivity of LTT in DRESS: analysis of agreement with the Spanish pharmacovigilance system probability algorithm Rosario Cabañas, Elena Ramirez, Ana María Fiandor, Teresa Bellón P163 The role of interleukin-22 in β-lactam hypersensitivity Andrew Sullivan, Paul Whitaker, Daniel Peckham, B. Kevin Park, Dean J. Naisbitt P164 Vancomycin-specific T cell responses and teicoplanin cross-reactivity Wei Yann Haw, Marta E. Polak, Carolann Mcguire, Michael R. Ardern-Jones Poster walk 19: BAT and biomarkers (P165–P173) P165 A combination of early biomarkers useful for the prediction of severe ADRs Yumi Aoyama, Tetsuo Shiohara P166 Basophil activation test in the diagnostic approach of reactions during general anaesthesia Ana Moreira, Susana Cadinha, Patrícia Barreira, Ana Castro Neves, Daniela Malheiro, Sara Correia, J. P. Moreira Da Silva P167 IL-10 can be related to successful desensitization Asli Gelincik, Semra Demir, Fatma Sen, Hamza Ugur Bozbey, Muge Olgac, Derya Unal, Raif Coskun, Bahauddin Colakoglu, Suna Buyuozturk, Esin Çatin-Aktas, Gunnur Deniz P168 Immediate reactions to proton pump inhibitors: value of basophil activation test Maria Salas, Jose Julio Laguna, Esther Barrionuevo, J. Dionicio, Tahia Fernandez, R. Gonzalez-Mendiola, I. Olazabal, Maria Dolores Ruiz, Miguel Blanca, Cristobalina Mayorga, Maria José Torres P169 Improvement of the elevated tryptase criterion to discriminate IgE from non-IgE mediated allergic reactions Gabriel Gastaminza, Alberto Lafuente, Carmen D’Amelio, Amalia Bernad, Olga Vega, Roselle Catherine Madamba, M. Jose Goikoetxea, Marta Ferrer, Jorge Núñez P170 Low expression of Tim-3 could serve as a biomarker for control and diagnose maculopapular exanthema induced by drugs Tahia Diana Fernández, Inmaculada Doña, Francisca Palomares, Rubén Fernández, Maria Salas, Esther Barrionuevo, Maria Isabel Sanchez, Miguel Blanca, Maria José Torres, Cristobalina Mayorga P171 Role of basophil activation test using two different activation markers for the diagnosis of allergy to fluoroquinolones Esther Barrionuevo, Tahía Fernandez, Arturo Ruiz, Adriana Ariza, Maria Salas, Inmaculada Doña, Ana Molina, Miguel Blanca, Maria Jose Torres, Cristobalina Mayorga P172 The importance of basophil activation test in anaphylaxis due to celecoxib Amalia Bernad Alonso, Carmen D’Amelio Garófalo, Olga Vega Matute, Marta Ferrer Puga, María José Goikoetxea Lapresa, Roselle Catherine Yu Madamba, Gabriel Gastaminza Lasarte P173 The role of basophil activation test in the diagnosis of immediate type drug hypersensitivity to betalactam antibiotics Antonia Thinnes, Hans F. Merk, Jens Malte Baron, Martin Leverkus, Galina Balakirski Poster walk 20: TCR recognition, cellular (P174–P183) P174 Characterisation of the effect of co-inhibitory signalling on the activation of drug-derived antigen-specific T-cells Andrew Gibson, Monday Ogese, Lee Faulkner, B. Kevin Park, Dean J. Naisbitt P175 Characterization of drug hapten-specific T cell responses in piperacillin hypersensitive patients Zaid Al-Attar, Fiazia Yaseen, Xiaoli Meng, Rozalind Jenkins, Paul Whitaker, Daniel Peckham, Lee Faulkner, John Farrel, Kevin Park, Dean Naisbitt P176 Characterization of the response of T-cells to telaprevir and its metabolite in normal volunteers Zaid Al-Attar, Khetam Alhilali, Yanni Xue, John Farrell, Lee Faulkner, Kevin Park, Dean Naisbitt P177 Characterization of the T cell receptor signatures of drug-responsive T cells Patricia Illing, Nicole Mifsud, Heidi Fettke, Jeffrey Lai, Rebecca Ho, Patrick Kwan, Anthony Purcell P178 Defining the signals between hepatocytes and immune cells in idiosyncratic drug-induced liver injury (DILI) Monday O. Ogese, Lee Faulkner, B. Kevin Park, Catherine Betts, Dean J. Naisbitt P179 Development of novel chemicals that do not bind to HLA-B*57:01 or activate CD8 + T-cells through modification of the 6-amino cyclopropyl group of abacavir Paul Thomson, John Farrell, Mohammad Alhaidari, Neill Berry, Paul M. O’Neill, B. Kevin Park, Dean J. Naisbitt P180 Generation and characterization of dapsone- and nitroso-dapsone-specific T-cell clones using lymphocytes from healthy volunteers Abdulaziz Alzahrani, Monday O. Ogese, John Farrell, Lee Faulkner, Andrew Gibson, Arun Tailor, B. Kevin Park, Dean J. Naisbitt P181 Identification of benzylpenicillin-hapten peptides responsible for naïve T-cell activation and immunization of allergic patients to penicillin Marie Eliane Azoury, Lucia Fili, Rami Bechara, Noémie Scornet, Cathy Nhim, Richard Weaver, Nancy Claude, Delphine Joseph, Bernard Maillere, Paola Parronchi, Marc Pallardy P182 Massive expansion of clonotypic and polycytotoxic CD8+ T cells in toxic epidermal necrolysis Axel Patrice Villani, Aurore Rozières, Benoît Bensaïd, Mathilde Tardieu, Floriane Albert, Virginie Mutez, Tugba Baysal, Marc Pallardy, Janet Maryanski, Jean-François Nicolas, Osami Kanagawa, Marc Vocanson P183 Pharmaco-immunological synapse of HLA-drug-TCR in SCAR Shuen-Iu Hung Poster walk 21: new in vitro methods, haptens, etc. (P184–P194) P184 Amoxicillin-clavulanate forms distinct multiple haptenic structures on human serum albumin in patients Xiaoli Meng, Arun Tailor, Caroline J. Harrison, Rosalind E. Jenkins, Paul Whitaker, Neil S. French, Dean J. Naisbitt, B. Kevin Park P185 Dendrimeric antigens for studying the influence of penicillin determinants orientation on IgE recognition Maria Isabel Montañez, Cristobalina Mayorga, Francisco Najera, Adriana Ariza, Tahia D. Fernandez, Maria Salas, Angela Martin-Serrano, Miguel Blanca, Ezequiel Perez-Inestrosa, Maria Jose Torres P186 Dendrimeric antigens on solid supports: designed materials for IgE quantification Yolanda Vida, Maria Isabel Montañez, Noemi Molina, Daniel Collado, Francisco Najera, Adriana Ariza, Maria Jose Torres, Cristobalina Mayorga, Ezequiel Perez-Inestrosa P187 Development of a screening assay for drug hypersensitivity using naïve T cells from donors with seven different HLA class I risk alleles Lee Faulkner, Sally Wood, Ana Alfirevic, Munir Pirmohamed, Dean J. Naisbitt, B. Kevin Park P188 Different patterns of recognition of structures derived from amoxicillin by IgE antibodies from patients with immediate hypersensitivity reactions to betalactams Adriana Ariza, Cristobalina Mayorga, María Isabel Montañez, María Salas, Inmaculada Doña, Ángela Martín-Serrano, Ezequiel Pérez-Inestrosa, Dolores Pérez-Sala, Miguel Blanca, Antonio E. Guzmán, María José Torres P189 High-resolution typing of HLA polymorphism and T-cell receptor repertoire for severe adverse drug reactions based on the cost-effective next-generation sequencing approaches Tai-Ming Ko, Yuan-Tsong Chen, Jer-Yuarn Wu P190 Identification and fate of intracellular proteins haptenated by amoxicillin Francisco J. Sánchez-Gómez, Juan M. González-Morena, Yolanda Vida, Ezequiel Pérez-Inestrosa, Miguel Blanca, María J. Torres, Dolores Pérez-Sala P191 In vitro detection of terbinafine protein adducts Arun Tailor, Toru Usui, Yanni Xue, Xiaoli Meng, Dean J. Naisbitt, B. Kevin Park P192 MicroRNAs dysregulation in PBMCs from drug hypersensitivity patients during drug challenge in vitro Alejandra Monroy Arreola, Jesus Agustin Badillo Corona, Silvia Mendez Flores, Judith Dominguez Cherit, Dean J. Naisbitt, Noe Valentin Duran Figueroa, Jose Luis Castrejon Flores P193 NSAIDs-exacerbated cutaneous disease: high throughput gene expression profiling José Antonio Cornejo-García, James Perkins, Natalia Blanca-López, Diana Pérez-Alzate, Raquel Jurado-Escobar, Inmaculada Doña, Gador Bogas, María J. Torres, Gabriela Canto, Miguel Blanca P194 Utility of skin tests in non-immediate reactions to amoxicillin Luis Mario Tubella Marti, Fernando Pineda De La Losa, Francisca Arribas Poves, Jaime Tubella Lopez, Teodora Lopez Santiago


Fig. 2 Causative proton pump inhibitors, demographic data, and allergologic investigation of patients with PPI-SCARs
Background: β-lactam antibiotics are commonly prescribed drugs worldwide and the most frequent cause of adverse drug reaction mediated by immunological mechanisms. Nonimmediate reactions, specially maculopapular and urticarial exanthems, are common. Skin tests are used to evaluate drug hypersensitivity and delayed reading might be useful in the diagnosis. Report: A 2.5 year old girl, with no relevant past medical history, was referred to our outpatient clinic for suspected drug allergy to β-lactams. The patient had been admitted to the hospital for acute mastoiditis. Upon admission, amoxicillin-clavulanic acid (Ax/C), which she had been taking for 4 days, was discontinued due to vomiting and she was started on triple IV antibiotherapy with ceftriaxone, vancomycin and metronidazole. On the 15th day of treatment, physical examination revealed a diffuse pruriginous maculopapular rash and fever, without palpable adenopathies. C-reactive protein was increased, eosinophil count was within normal range values and serologies for EBV and CMV were negative. An allergic reaction to ceftriaxone was suspected and the drug was discontinued by the 23rd day of treatment. Due to persistence of symptoms, the remaining 2 antibiotics were also discontinued 3 days later. Skin biopsy was suggestive of Clin Transl Allergy 2016, 6(Suppl 3):30 erythema multiforme and a course of systemic corticotherapy was started with resolution of symptoms. Skin prick tests and intradermal tests (IDT) with Ax/C, penicillin, cefuroxime and ceftriaxone were performed, using the maximal non-irritant dose, all of which were negative on immediate reading. 48 h later, both the prick and IDT were positive for Ax/C as well as the IDT for ceftriaxone. How this report contributes to current knowledge: Few nonimmediate reactions to cephalosporin are confirmed, due to the fact that most are caused by infections. Nonetheless, allergic reactions can occur even in young children, and in our case, the culprit agents were confirmed by a positive skin prick test on delayed reading. Skin prick tests and IDT with delayed readings seem to be useful in the evaluation of these reactions.

Consent:
Written informed consent was obtained from the patient for publication of this abstract and any accompanying images.
Patients with allergic reactions after AX-CLV administration can react to either AX or CLV. No evidence of cross reactivity between CLV and other BL has been reported. Report: We present an atopic 44 year-old man referred to our allergy unit due in 2008 he took amoxicillin 500 mg/day as treatment for respiratory infection, 30 min after the first tablet he developed pharyngeal pruritus, cutaneous erythema and flushing following generalised itching and erythema. Method: Skin prick test (SPT) and intradermal test (IDT) were performed using classic penicillin determinants, amoxicillin, ampicillin and clavulanic acid determinants according ENDA protocol. Total IgE and specific IgE (Thermo Fisher Scientific) with penicillin determinants (penicilloyl G, amoxicilloy, penicilloyl V and ampicilloyl) were performed. Drug provocation Test (DPT) if skin and in vitro test were negatives. As reaction was several years before, we performed second work up 1 month later. Results: Total IgE 270 KU/l, Specific IgE with penicillin determinants were negative. Skin tests show positive results only to CLV (20 mg/ml IDT). DPT was positive to AX, 30 min after first dose (125 mg) patient developed pruritus, facial erythema and cutaneous rash in thorax and back. DPT with BP following 3 days domiciliary intake was negative. Second work up. Skin tests show positive results only to CLV 20 mg/ml IDT. DPT and with BP following 3 days domiciliary intake was negative again. How this report contributes to current knowledge Conclusions We present a double selective sensitization to clavulanic acid and amoxicillin with tolerance to BP. We confirm that tolerance to BP is a stable phenomenon performing a second BP administration 1 month later, according recently studies,  (2) 6-9 años 0.58 (2) 0.58 (2) 1.46 (5) 1.17 (4) 0.59 (2) 10-14 años 1.36 (6) 0.91 (4) 0.23 (1)  where selective patients tolerate subsequent administrations of other BL. Our exceptional case highlights the need to be aware of new patterns of beta-lactams sensitization. We recommend using AX and CLV separately for skin test.
Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Background: Infliximab (IFX) carries potential risk of immunogenicity, with the expansion of memory T cells and the production of anti-drug antibodies (ADA). Little is known about the possibility that sensitization to IFX may occur also in treated ADA− patients. This study was aimed to evaluate whether IFX may be immunogenic in the latter group of patients. Materials and methods: Seventy-one IFX-treated patients, including both ADA+ and ADA− patients were enrolled. Untreated patients and healthy donors were also selected as controls. Memory T cells was evaluated by the proliferation of drug-stimulated PBMC or cocultures of IFX-pulsed DC plus autologous CD4+ T cells. Measurement of drug-induced cytokines production was performed in the culture supernatants by ELISA. Cytokines mRNA expression was also studied. Results: T cell proliferation and cytokine production were mainly detectable in ADA+ patients, but cytokines were observed in about 25 % of non-proliferating cultures as well. IL-10 was the most frequently detectable cytokine. Additionally, the proportion of patients expressing IL-10 mRNA in IFX-stimulated PBMC was significantly higher in ADA− than in ADA+ patients. IL-10 mRNA levels resulted higher in ADA− than in ADA+ patients. Anti-IL-10 mAbs were able to significantly increase both IFX-driven proliferation and expression of T cell-related cytokines in PBMC. Conclusions: Cell sensitization to IFX may be detectable in a proportion of ADA− treated patients. Proliferation assay combined with cytokines evaluation may work better than the single test in evaluating cell sensitization. In ADA− patients IFX-induced IL-10 may overcome the effects of other T cell-related cytokines. Background: Adalimumab, recombinant fully humanized anti-tumor necrosis factor (anti-TNF) antibody, had been using for the patients with inflammatory artritis and bowel diseases. Adverse reactions to adalimumab are limited mainly to injection site, immediate systemic reactions are very rare. Generalise skin reactions to this antibody are around 1 %. Certolizumab is humanized from mouse, anti-TNF recombinant antibody with the same indications. Systemic adverse reactions to certolizumab is very rare, also. Report: We report a 59-year-old woman with spondylartritisi (SpA) who was treated with adalimumab every 2 weeks for 4 years. At the 4th year, adalimumab was changed to prefilled ready to use form.

Poster
30 min after the first application of this form, local reaction and also vomiting, dispnea, laryngeal edema, hipotension with generalise itching happened. Than adalimumab was stopped. Therapy was changed to certolizumab pegol. 30 min after the first injection of certolizumab, she had nause, dizziness and visual disturbances without skin reactions. 15 days later she injected the second certolizumab dosage and the same reactions repeated. She was referred to allergy clinic. Skin prick test with 50 mg/ml of adalimumab was found negative. Intradermal test with (5 mg/ml) 1/10 dilusion was 10/45 mm and 1/100 dilusion was 8/40 mm (histamin intradermal: 10/50 mm). Both skin prick and intradermal tests with certolizumab pegol were negative. Depending on the uncertainty of her history about certolizumab, drug provocation test was administered with total therapy dose. No adverse or allergic reaction occured during provocation. The patient was continued certolizumab therapy seamlessly. How this report contributes to current knowledge: Although adverse systemic reactions to adalimumab are rare, we describe a immediate systemic reaction to adalimumab; fully humanized recombinant biological. We thought the reaction was not due to the new form, because the contents are completely same. Allergic reaction after changing the form seems to be coinsidental. Alternative monoclonal antibodies should be searched for those patients.

Consent:
Written informed consent was obtained from the patient for publication of this case report and any accompanying images.
Background: Although true allergy to local anesthetics (LA) is rare, patients often report unwanted reactions after the administration of LA, requiring allergy consultations. Diagnosis of hypersensitivity reaction to LA is made after skin tests followed by exposition tests. The aim of this study was to determine the negative predictive value (NPV) of skin tests to LA. Materials and methods: A retrospective chart review was performed on patients undergoing local anesthetic skin testing. A total of 50 patients tested for hypersensitivity to LA in the period from January to August 2015 at the Division of Clinical pharmacology at the University Hospital Zagreb were enrolled in this study. All patients underwent skin tests ('prick' and intradermal tests with 1:100 dilution) followed by incremental subcutaneous challenge with undiluted LA. Skin tests were performed with lidocaine, articaine, bupivacaine or articaine + adrenaline, while exposition was performed using mainly lidocaine. Telephone follow-up visits were performed during December 2015. On the basis of the follow-up results, the NPV of skin tests was calculated.
Results: Skin tests were performed using two or more LA (lidocaine in 50 patients, articaine in 35 patients, bupivacaine in 27 patients, articaine + adrenaline in 11 patients). All skin tests were negative. Subcutaneous challenge was performed with lidocaine in 41 pts, articaine in 7 pts, bupivacaine in 1 pt, and articaine + adrenaline in 1 pt. All patients had negative subcutaneous challenge. In the follow-up period 20 pts received LA, 20 pts have not received LA while 10 pts were unavailable for follow-up. Of the patients who received LA after testing, 19 had no reactions during exposure while 1 pt experienced a severe hypertensive reaction with generalized exanthema. The NPV of skin tests to LA was 95 %. NPV for subcutaneous challenge tests was not calculated due to incomplete data on specific LAs used in subsequent exposures. Conclusions: Skin tests to LA are safe and have an excellent negative predictive value which allows the selection of a local anesthetic that can be safely administered in the future. Keywords: Local anesthetics; Skin test; Hypersensitivity; Negative predictive value Background: Local anesthetics, such as lidocaine, are widely used for numbing. Adverse drug reactions related to lidocaine are variable, unpredictable, and rarely reproducible, with the exception of some typical cases. Report: A 42-year-old female who had shown a bizarre neurological reaction after lidocaine injection for dental procedures was referred for diagnosis and safe anesthetic alternatives. Within a few minutes after exposure to lidocaine, she was unable to move any extremity, or to speak, while sensory and high cranial nerve functions were preserved. She was alert and able to communicate with eye blinks. This reaction was repeatedly reproduced after intradermal injection of 2 % lidocaine, with complete recovery within 1 h without treatment. No cross-reactivity with mepivacaine and bupivacaine was observed.
How this report contributes to current knowledge: This is the first report of immediate and transient generalized paralysis related to lidocaine.

Consent:
Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. . Only 5 patients (7.7 %) had positive DPT (lidocaine in 2 patients, mepivacaine in 2 patients and ropivacaine in 1 patient). Of those patients, 60 % were female and the median age was 35 years (±20.6 years). Sixty percent of the patients had past history of multiple surgical interventions (with general anesthesia) and allergic diseases, asthma and rhinitis being the most frequent. Cutaneous symptoms (urticaria and angioedema) were the main manifestation, in 4 patients (66 %). There was no registry of severe adverse reactions. All reactions started within 2 h following LA application and regressed spontaneously without any treatment. Sensitization to both lidocaine and mepivacaine was determined in 2 patients. Comorbidities such as hypertension (2 patients), diabetes (1 patient) and thyroid disease (1 patient) were also seen. Eighty-three percent of these reactions occurred during dental procedures and 60 % of these after administration of lidocaine.

Conclusions:
As stated in other studies, we find a low positivity rate to DPT. And our findings were similar to those found in the literature: adverse reactions to LA are more prevalent in the mid-age and with cutaneous symptoms being the most frequent manifestation of HS. Although rare, consequences of true allergy to local anaesthetics can be serious, considering a patient's future management and therapy. Background: A 44 year-man was urgently admitted to our allergy clinic with complaints of pain in the area of scrotum, painfulness in oral cavity, rash on hands, eyelids and foot. Anamnesis excerption: Alcohol abuse for a long time. About 2 years ago, following one of patient's drinking-bouts, episode with loss of consciousness emerged, qualified as secondary epilepsy; carbamazepine was administered. The patient described vesicular rash on lips and hands following the carbamazepine medication; he did not seek medical attention, though. The therapy was cancelled. Within 2 weeks the skin rash passed. The present episode had also been related with a prolonged period of alcohol ingestion, whereupon a detoxification treatment was administered, and, taking into account the possibility of episyndrome, carbamazepine was ordered, too. On the second day vesicular rash appeared on hands, thereupon in the scrotum area, on eyelids and on mucous tunic of mouth, forcing the patient to seek medical attention. One month later, the patient underwent another cardiac catheterization. However, 10 min after the administration of 15 g of Iodixanol, he presented another episode of anaphylactic shock. He was given the same medications he had received previously which reversed the anaphylactic shock. Tryptase level was positive (30.20 μg/l). Due to the episode of anaphylactic shock, the contemplated cardiac catheterization was discontinued. Skin tests the next day resulted positive to Iohexol, Iodixanol and Iomeprol. How this report contributes to current knowledge: Despite that the patient tolerated well the challenge test with Iodixanol and skin test was negative, possible hypersensitivity reactions can still occur. Although challenge test is considered the gold standard in drug allergy, it can also provoke sensitisation to the drug or increase the sensitivity that could not be detected prior due to cross reaction. As of the present, the pathophysiological mechanism of these allergic reactions still needs to be exemplified.

Consent:
Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Background: Gadobenate Dimeglumine and Gadoteric Acid are two gadolinium-based contrast agents that enhance the contrast images obtained by magnetic resonance imaging. Allergic reactions to them are rare. Materials and methods: We report two cases of IgE-mediated anaphylactic shock, induced by these gadolinium-based contrast agents and documented by positive allergy assessment. The first case is a 26-year-old woman with no previous drug allergy who developed dizziness, generalised erythrodermia and throat tightness, when a nuclear magnetic resonance with MultiHance (Gadobenate Dimeglumine) was being performed. On physical examination, she had hypotension, tachycardia, tachypnea, 69 % of basal oxygen saturation and generalized pulmonary hypoventilation. She recovered after treatment with corticosteroids and adrenaline. Nine months later the patient was referred to the allergy unit. The second case is a 51-yearold woman with a history of high blood pressure treated with betablockers, rhinoconjunctivitis and asthma due to sensitization to house dust mites and dog dander. Immediately after the intravenous infusion of Dotarem (Gadoteric Acid) she developed dizziness, loss of consciousness and cardiac arrest. On physical examination, she had universal rash without wheals, 90 % of basal oxygen saturation and generalized wheezing. CPR was started and 1 mg of Adrenaline was administrated. She recovered after 15 min and was admitted to the ICU. Two months later she was referred to the allergy unit. Results: Case 1: Basal serum tryptase was normal. Skin prick tests (SPTs) were positive with Gadobenate Dimeglumine and negative with other paramagnetic contrasts agents and latex. The patient tolerated an MRI with Gadobutrol 2 years later. Case 2: Basal serum tryptase was normal. Basophil activation test (BAT) was positive with Gadoteric Acid, and negative with other paramagnetic and iodinated contrast agents.

Conclusions:
We report two cases of an anaphylactic shock, one with cardiac arrest, immediately after the intravenous infusion of a paramagnetic contrast agent. Positive SPTs to Gadobenate Dimeglumine and positive BAT to Gadoteric Acid suggest an IgE-mediated mechanism. Hypersensitivity reactions with paramagnetic contrasts are very unusual. There are few cases with positive SPTs or BAT reported in literature. We should take into account that SPTs and BAT can be helpful to identify the responsible agent and the alternative contrasts that could be administered safely to the patient in the future. Keywords: Paramagnetic contrast agents; Anaphylaxis Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. As relapses were frequent despite treatment, this was changed in January/2013 to natalizumab (Tysabri ® ), which is a monoclonal antibody (α4-integrin antagonist) with similar therapeutic indications to those described for GA. After 12 months of treatment, natalizumab was stopped because the patient developed persistent anti-drug antibodies. Considering that the patient was planning a pregnancy a new treatment (with GA) was started in March/2015. Four months later, the patient presented a generalized skin-burning sensation, dyspnoea and palpitations, 1 min after GA administration with no additional signs or symptoms. At this point, the patient was referred to our Drug Allergy Department for assessment. Skin tests were performed with GA plus the inactive ingredient of Copaxone ® with allergenic potential, mannitol; the dilutions were prepared with saline solution. For skin prick tests we used GA 20 mg/ml in the 1/100, 1/10 and 1/1 dilutions, and mannitol 100 mg/ml (undiluted). Intradermal tests were performed with 1/1,000,000-1/10 dilution of GA (20 mg/ml), with a strong positive result at 1/10 concentration. Intradermal test to mannitol (1/10 dilution) was negative. How this report contributes to current knowledge: We also tested three (2 atopic and 1 non-atopic) controls for GA at 1/10 dilution with negative results. These results point to an underlying immunological mechanism in this case. A desensitization approach with GA might be considered for this patient.

Consent:
Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Background: Iodinated contrast media (ICM) may associate with different types of adverse events including allergic and non-allergic hypersensitivity reactions as defined by the European Academy of Allergy and Clinical Immunology. Immune-mediated reactions are either immediate or non-immediate reactions that become apparent later than 1 h (and up to several days) after exposure and these are less frequently reported. Report: The authors report the case of a 46 year-old woman, with history of Hodgkin's lymphoma, evaluated in our Drug Allergy Unit for two suspected hypersensitivity reactions to ICM. In 2014, the patient underwent a contrasted CT scan with iomeprol (Iomeron ® ) and 72 h later developed a generalized pruritic micropapular exanthema that resolved completely in a week (with antihistamine and corticosteroid medication). She had been previously exposed to ICM with tolerance. In 2015, a new high-resolution CT scan was performed using the same ICM (iomeprol), and again a diffuse pruritic exanthema developed (6 h later) but this time with facial angioedema and fever (39 °C); the symptoms resolved in 4 days under medication (antihistamine and corticosteroid), leaving residual purplish lesions that eventually disappeared (after weeks). Skin prick tests with idopovidone (Betadine ® ), and undiluted ioversol (Optiray ® ), iobitridol (Xenetix ® ), iopromide (Ultravist ® ) and iomeprol (Iomeron ® ) were negative. Intradermal tests were performed with 1/100 and 1/10 dilutions of ioversol (Optiray ® ), iobitridol (Xenetix ® ), iopromide (Ultravist ® ) and iomeprol (Iomeron ® ); immediate reading was negative for all tested ICM but late reading (at 48 h) was positive to ioversol (Optiray ® ) and iomeprol (Iomeron ® ) in both dilutions. How this report contributes to current knowledge: The results confirmed a delayed hypersensitivity to ICM, with cutaneous cross-reactivity between ioversol and iomeprol.

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Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. The contrast used for catheterization was iodixanol. The patient also received ticagrelor, carvedilol, enalapril, furosemide, fondaparinux and lorazepam. Assessment of causality was established using the Spanish Pharmacovigilance System Algorithm. Results were (+6) "probable" for iodixanol and (+4) "possible" for carvedilol and ticagrelor. A multidisciplinary group composed by a dermatologist; a pharmacologist and an allergist evaluated the patient. This case was included in the Piel en RED registry. Six months after the reaction the patient was referred to the allergy unit and tests were performed. The allergy study included epicutaneous tests and the lymphocyte transformation test (LTT) according to Pichler et al. An stimulation index (SI) was calculated. Results: The diagnosis of a "probable" DRESS was established according to the scoring system described by Kardaun et al. Our patient received a score of 4. A skin biopsy showed spongiotic dermatitis with eosinophils. The patient had a positive LTT to iodixanol; the SI was over 8 in two concentrations. LTT showed also positive results for other iodinated contrast media. We also tested carvedilol and ticagrelor with a lightly positive result. Epicutaneous test showed remarkable positivity to iodixanol beginning at the 48 h reading. The test was negative to carvedilol, iobitridol and iomeprol. How this report contributes to current knowledge: LTT and patch test were useful to identify this agent as responsible for the reaction. DRESS requires a multidisciplinary approach and an allergy study is essential to determine the etiology of the disease.

Consent:
Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. , urticaria (20 %), angioedema (13.3 %) and pruritus (6.7 %) to ICM. One pt had positive skin tests to iodixanole and negative to iohexole. All other performed tests were negative. In the follow-up period 4 pts were exposed to ICM without adverse reactions; 10 pts were not exposed to ICM; 1 pt was unavailable for follow up. The immediate group comprised 11 pts with hystory of gastrointestinal symptoms (27.3 %), urticaria (27.3 %), angioedema (18.2 %), general symptoms (18.2 %) and flush (9.1 %) to ICM. One pt tested positive to iohexole. All other performed tests were negative. In the follow-up period 7 pts were exposed to ICM; 6 pts experienced no adverse reactions; 4 pts were not exposed to ICM and 1 pt developed angioedema. The previously unexposed group comprised 14 pts. All skin tests were negative. The reason for referral to ICM testing was a hystory of serious allergic reaction to different allergens. In the follow-up period 5 pts were exposed to ICM without adverse reactions; 4 pts were not exposed to ICM; 5 pts were not available for follow up. Conclusions: Overall, 16 pts were exposed to ICM in the follow-up period and of those, 1 pt developed an immediate reaction. Background: Allergies to povidone iodine (PVI) are related to povidone (PV), those due to radio contrast media (RCM) to cyclic structures and those with seafood related to animal protein such as tropomyosin.

P126 Electronic consultation support system for radiocontrast media hypersensitivity changes clinician's behavior
The iodine allergy is a mythical entity, but nevertheless! Materials and methods: A 39 year old diabetic man, with end stage renal disease undergoing peritoneal dialysis, was referred for immediate hypersensitivity (IH) reactions. Betadine dermique ® containing povidone iodine triggered an immediate contact pruritic rash disappearing in 30 min (mns). Angioedema and urticaria occurred a few mns after ingestion of shrimps, mussels, oysters, whelks, trout and salmon. Awaiting kidney transplant, having never received RCM, a predictive assessment of RCM IH was required. Patch and prick tests (pt), IDT, specific IgE and RCM reBackground were performed under hospital supervision. Results: While all patch tests were negative, pt were positive for pure Betadine dermique ® and iodized alcohol at 1 % in water but negative for Lugol 2 % (potassium iodide) and PV. Pt to a native oyster was positive but negative for crab, mussel and shrimp. IgEs were negative for salmon, mussel, oyster and shrimp. Pt and IDR were negative for iobitridol, ioxaglate and iodixanol in pure form (use concentration), but the intravenous administration of 1 ml iobitridol induced a generalized pruritus, a trunk and face erythema with ear edema, occurring after 30 mns and resolution in 60 mns after treatment with intravenous methylprednisolone and antihistamines.
Conclusions: This exceptional case of multiple reactivities to iodine products and oyster suggests that for this patient iodine itself could be the common allergen. The positive pt to oyster is probably not related to a tropomyosin sensitization. Unlike previous published cases of allergy to povidone iodine, in this case the IH does not appear due to PV. While IDT was negative, iobitridol induced an immediate reaction. We emphasize (1) in case of PVI IH, the need to do a pt to PVI and PV before concluding to the lack of iodine sensitization and thus allow RCM; (2) if negative IDT with RCM, we must continue investigations by an intravenous Background test with a limited volume of RCM and (3) even if it is exceptional, an iodine allergy may exist. Investigations are continued with in vitro tests. Keywords: Allergy; Iodine; Multiples reactivity Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images.
Background: Drug hypersensitivity reactions represent a heterogeneous clinical entity with diverse pathogenesis and result in a considerable burden of morbidity and mortality. Diagnostic procedures rely on clinical history, skin testing and in some cases, provocation tests.
Drug imputability is still difficult to establish due to the weakness of sensitivity of some skin tests and the impossibility to perform provocation test in case of severe reactions. The aim of our study is to evaluate delayed-type cutaneous allergic reactions associated with drug use.

Materials and methods:
The data were obtained from a Tunisian pharmacovigilance database of adverse drug reactions (ADRs). Analyzed reports were retrieved from the pharmacovigilance unit of Monastir (Tunisia) database collected from 2004 to 2015. The association between drugs and skin reactions was assessed using the case/ non-case method, calculating the adverse reaction reporting odds ratio (ROR) and their 95 % confidence intervals as a measure of disproportionality. The "cases" were defined as reports of type III and IV skin allergic reactions (according to gelle and Coombs classifications). The "non-cases" were all other reports. Background: Delayed hypersensitivity reactions to cephalosporins are poorly described reactions that occur more than 1 h after drug administration. The mechanisms involved seem to be heterogeneous and not totally characterized. Objectives: To characterize the delayed hypersensitivity to cephalosporins and determine the clinical profile of these patients and the cross reactivity with other antibiotics.

Materials and methods:
Retrospective review from the patients with delayed confirmed hypersensitivity reactions to cephalosporins between 2013 and 2014. The patients were submitted to skin tests with penicilloylpolylysine (PPL), minor determinant mixture (MDM), benzylpenicillin, ampicillin, amoxicillin, cefuroxime, ceftriaxone, cefipime and other antibiotics that were eventually involved. Results for specific IgE to β-lactams and oral provocation challenge tests (OPT) with the alternative and/or culprit β-lactms were also reviewed. Results: Within the 7 patients that were reviewed 71 % were female, with a median age of 56 (32.5-66) years and 43 % had personal history of atopy. The clinical manifestations reported by these patients were delayed urticaria in 57 % of the cases and 43 % described delayed rash. In all cases the symptoms appeared more than 24 h after the beginning of the antibiotic. In 6 (85.7 %) the episodes occurred after cephalosporins intake. One patient had an adverse event with amoxicillin and the sensitization to cephalosporins was only found after investigation. All had negative specific IgE for β-lactams. Four (57.1 %) had sensitization only to cephalosporins. The cephalosporins involved and the delayed results of the IDT and OPT are summarized on Background: Allergic contact dermatitis is an immune-mediated antigen-specific skin reaction to an allergenic chemical that corresponds to a delayed-type hypersensitivity response (type IV reaction). Allergic contact dermatitis should be suspected when skin lesions are localized to the site of previous applications of the culprit drug. The gold standard for diagnosis is patch testing; identification and removal of any potential causal agents is crucial. Diclofenac cream/gel contains propylene glycol, diclofenac, dimethyl sulfoxide, ethanol and glycerin. It is a widely used non-steroidal antiinflammatory drug, known to cause especially photoalergic contact reactions. Report: We present four cases of diclofenac induced allergic contact dermatitis, diagnosed based on clinical grounds: intensly itchy eczematous lesions on the sites of drug application, after several days of treatment. No allergic history, no other drug intake were reported by the patients. The application of topical diclofenac was strictly avoided in all cases, potent topical steroids proved to be effective in all cases within two weeeks of therapy. Patch tests were performed in all cases with European standard batery and with patients' own cream or gel 3 weeks after completion of local steroid therapy. Reading was performed at 96 h and proved to be positive only to diclofenac. No sun exposure was allowed during the testing, any other treatments were forbidden. How this report contributes to current knowledge: Patients and physicians must be aware of the risk of cutaneous sensitization induced by topical diclofenac, a drug extensively used also as self medication. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Background: Hypertension is one of the most common worldwide diseases. Angiotensin II receptor blocker are one of antihypertensive drugs most prescribed. Some well-known adverse effects of irbesartan are dizziness, urticaria and angioedema. Irbesartan cutaneous nonimmediate reactions have been reported previously in a limited number of case reports. Report: Sixty years old female patient referred to our clinic with a 3 week history of an itchy erythematous maculopapular eruption affecting the torso (thorax and abdomen) and proximal part of upper and lower limbs which resolved with hyperpigmentation. The patient reported since then similar but short-lasting lesions that she related to atorvastatin intake. The patient current medications were: atorvastatin, irbesartan, chlordiazepoxide, levothyroxine, estradiol patch, olanzapine and paroxetine. All of them but irbesartan and paroxetine had been taken for several years. Irbesartan was the latest drug introduced, approximately 2 months before the exanthematous rash beginning and paroxetine was only introduced after the symptoms appearance. There was no history of any infectious disease. Previously performed histopathologic examination of the lesions showed lymphocytic infiltrate and eosinophils in the dermis, compatible to drug reaction. Irbesartan was changed to diltiazem in patient therapy. Patch tests (PT) to irbesartan, candesartan and atorvastatin (5 % in petrolatum) were performed and a lymphocyte transformation test (LTT) to irbesartan was executed. Results: PT to irbesartan was positive at 48 and 96 h. LTT (irbesartan 100 µg/ml) showed 6.3 stimulation index. The patient did not refer new lesions after stopping irbesartan and was diagnosed as non-immediate drug reaction due to irbesartan based in clinical, histopathologic and analytic features. Three months later candesartan was introduced in patient therapy, without skin reaction after 3 months. How this report contributes to current knowledge: There are few reports about non immediate cutaneous side effects due to irbesartan. PT and LTT proved useful in the diagnosis. In spite of the similarity of chemical structure, candesartan may be tried in patients allergic to irbesartan. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Although direct contact with the skin is not always present, distribution of dust containing omeprazole through the air and deposition on exposed areas may result in an airborne pattern of contact dermatitis. Our case confirms the risk of sensitization to omeprazole from occupational exposure. Keywords: Omeprasole; Proton pump inhibitor; Eczema Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images.  (5); their patient had also shown a FDE following oral intake of fluconazole (5). In another case (6) cross-reactivity occurred following oral intake with secnidazole.

P132
A 40-year-old male patient presented with two pigmented lesions, one on the upper arm, and one with a central erosion on the glans penis. These had occurred since the intake of ornidazole (Tiberal ® , Laboratoires SERB, Paris, France) and budesonide (Entocort ® , AstraZeneca, Brussels, Belgium), 2 weeks previously. The provisional diagnosis of FDE was put forward. Materials and methods: Five weeks later, patch tests with ornidazole (tablet crushed and diluted 30 % in petrolatum) and budesonide (0.01 % in petrolatum) were performed on a residual pigmented lesion on the upper arm, and also on a non-lesional skin site as a control, using vander Bend Chambers ® (vander Bend, Brielle, The Netherlands).

Results:
Only the patch test with ornidazole on the residual pigmented lesion showed a positive reaction at day 4, while the control on the non-lesional skin remained negative. Discontinuation of ornidazole resulted in clearance of the lesions. Conclusions: In the unlikely event of a fixed drug eruption, clear identification of the culprit may be difficult, in particular when multiple medications are administered. Patch testing in a previously affected lesion may identify the causative agent, as in the present case. Keywords: Fixed drug eruption; Ornidazole; Patch testing Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images (Fig. 4).  Conclusions: Delayed adverse reactions to amoxicillin and amoxicillin clavulanate may be diagnosed by alternative tests such as basophil and lymphocyte activation tests when conventional in vivo and vitro tests show negative results. We hypothesize that specific IgG may induce anaphylactic reactions through basophil activation. Although the role of T cell activation is not clear, we observed a synergic effect of both drugs. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. Background: Fenofibrate is widely used in the treatment of hypercholesterolemia and hypertriglyceridemia. Cutaneous side effects such as pruritus, rash, urticarial lesions, but also cases of photosensitivity have been previously described (1)(2)(3). A 47-year old female patient presented with a severe vesicular eruption involving the sun-exposed body areas, except under the wristwatch. The face was only slightly affected to which she had applied a sunscreen. She had been taken several medications, i.e., fenofibrate (Lipanthyl ® , Mylan EPD, Wavre, Belgium), metformine (Metformax ® , Menarini, Zaventem, Belgium), spironolactone, and allopurinol (Zyloric ® , Laboratoires SMB, Brussels, Belgium). Materials and methods: Patch tests with the European baseline series and photo-patch tests with the European photo-patch test series were performed, using IQ Ultra ® Chambers (Chemotechnique Diagnostics, Vellinge, Sweden). Results: A strong positive photo-patch test to ketoprofen (D2 −, D4 +++, D8 +++) and also a positive patch test to benzophenone-3 (D2 +, D4 ++) were obtained. Conclusions: Photo-allergic contact dermatitis from ketoprofen often gives rise to simultaneous reactions to other nonsteroidal anti-inflammatory drugs (NSAIDs), sunscreens, and fragrance components (4), as well as to fenofibrate (5), which, administered systemically, may induce photosensitivity. The benzophenone moiety is responsible for the photosensitization reaction (3.5). Keywords: Fenofibrate; Patch testing; photo-allergic contact dermatitis; Systemic contact dermatitis Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images (Fig. 5). Background: Cross-intolerance to nonsteroidal anti-inflammatory drugs (NSAIDs) is a class of hypersensitivity reaction in which NSAIDsinduced urticaria and/or angioedema (NIUA) is the most frequent entity. It is thought to involve dysregulation of the arachidonic acid (AA) pathway. However, this mechanism has not been confirmed for NIUA. In this work we assessed copy number variations (CNVs) in 8 of the main genes involved in the AA pathway and their possible genetic association with NIUA. Materials and methods: CNVs in ALOX5, LTC4S, PTGS1, PTGS2, PTGER1, PTGER2, PTGER3 and PTGER4 were analyzed using TaqMan copy number assays. Genotyping was carried out by real time quantitative PCR. Individual genotypes were assigned using the CopyCaller ™ Software. Statistical analysis was carried out using GraphPad prism 5, PLINK, EPI-DAT and R version 3.1.2. Results: 151 cases and 139 controls were analyzed during the discovery phase and 148 cases and 140 controls were used for replication. CNVs in open reading frames were found for ALOX5, PTGER1, PTGER3 and PTGER4. Statistically significant changes in CNVs between NIUA and controls were found for ALOX5 (p c = 0.017) and PTGER1 (p c = 1.22E−04). Moreover, we described that there was not a correlation between the presence of a deletion in ALOX5 with the presence of a deletion in PTGER1 (R 2 = 0.274). Conclusions: This study represents the first analysis showing an association between CNVs in exonic regions of ALOX5 and PTGER1 and NIUA. This suggests an important role of CNVs in this pathology that should be further explored in future studies. Background: NSAIDs are the first cause of drug hypersensitivity reactions (DHRs), being those mediated by non-specific immunological mechanisms (cross-intolerance, CI) the most frequent. Skin is the most commonly affected organ and NSAIDs-induced urticaria/angioedema (NIUA) the most frequent clinical entity. Galectin-3 plays an important role in the biological responses of skin cells, and it is being regarded as a novel therapeutic target for a variety of skin disorders. We analyzed the association of several nonsynonymous single nucleotide polymorphisms (SNPs) in LGALS3 with CI in a large group of patients with different clinical entities, including NIUA, NSAIDs-exacerbated respiratory disease and a mixed pattern of response that includes both skin and respiratory involvement. Materials and methods: The population studied was obtained from two Allergy Services integrated into the Spanish network RIRAAF. Cases included had to develop more than two episodes of CI after the intake of two or more NSAIDs from different chemical groups. We studied several SNPs in LGALS3 using TaqMan ® probes. s both skin and respiratory involvement. Results: A total of 504 subjects with CI to NSAIDs were included and 271 age and sex-matched healthy controls. Statistically significant associations were found between NIUA and LGALS3 rs11125 (p < 0.001) and rs4644 (p = 0.032). Conclusions: Our results suggest a role for SNPs in LGALS3 in NIUA, the most important clinical entity induced by HRDs. The association of such genetic variants with NIUA provides us with new clues for understanding their underlying mechanisms. Further studies are required to analyze the potential role of other genetic variants in galectins and related genes in HRDs to NSAIDs. Background: Ticlopidine is an anti-platelet drug used in the treatment of atherothrombosis and is known to cause idiosyncratic drug induced liver injury (DILI). The recent identification of human leukocyte antigen (HLA)-A*33:03 as a susceptibility factor and the delayed nature of the liver injury are both indicative of an immune pathogenesis. However, the role of the adaptive immune system in ticlopidine-induced DILI has not yet been defined. The aim of this study was to investigate whether drug-specific T cell responses could be detected in healthy volunteers who expressed HLA-A*33:03. Any T cell responses would then be fully characterized for drug specificity, HLA restriction and the mechanism(s) of antigen presentation Materials and methods: Peripheral blood mononuclear cells were isolated from HLA-typed healthy volunteers who did or did not express the risk allele: HLA-A*33:03. Subsequently, naïve T-cells were separated and co-cultured with autologous monocyte-derived dendritic cells (DCs) in the presence of the ticlopidine for a period of 8 days, to expand the number of drug-responsive T-cells. T-cells were then harvested and incubated with freshly prepared dendritic cells and drug to test their antigen specificity using readouts for cell proliferation and cytokine secretion. T-cell clones were also generated following priming and drug-specific T cell clones analysed for cytokine secretion and HLA restriction. Results: Using the DC priming assay all four HLA-A*33:03 positive donors showed ticlopidine-specific proliferation and IFNγ secretion. However, no ticlopidine-specific responses were detected in HLA-A*33:03 negative donors. Around one thousand CD8 positive clones were generated from three HLA-A*33:03 positive donors, but ticlopidine specific clones were only obtained from one donor. These CD8 positive clones showed ticlopidine-specific IFNγ secretion. This response was restricted by HLA-A*33:03 and was not dependent on the presence of antigen presenting cells.

Conclusions:
In conclusion, ticlopidine-specific T-cells were detected in healthy volunteers expressing the risk allele HLA-A*33:03 using the DC priming assay. Background: A handful of genome wide association studies (GWASs) have been performed to detect genetic variation associated with NSAID hypersensitivity, by comparing the frequencies of hundreds of thousands of single nucleotide polymorphisms (SNPs) between NSAIDs hypersensitive subjects and control individuals. This is done on a SNP-by-SNP basis, meaning that each variant is considered independently. However, the effect of a single SNP on phenotype is influenced by other factors, including the individual's genetic background. An alternative approach to analyse this data is the use of epistasis methods, which look for associations between pairs of SNPs and a phenotype that are stronger than the sum of the individual SNP-phenotype associations, suggesting an interaction between the SNPs. Materials and methods: We analysed data from an NSAIDs hypersensitivity GWAS using an epistasis detection method, MBMDR. The resulting pairs of interacting SNPs were used to build networks, both at the SNP level and at the gene level, by mapping SNPs to their closest protein coding gene (within 500 kb). These networks were analysed to identify SNPs and genes with a potential role in NSAIDs hypersensitivity using graph metrics. This approach identifies important hub nodes based on the strength and number of connections they have, which can be interpreted as the number of distinct pair-wise interactions they are involved in. Results: Our approach identified a number of genes with potential roles in NSAIDs hypersensitivity, including genes potentially involved in asthma (KCNB2, PPP1R3C and CSMD1), rhinitis (SCN11A) and immune system functioning (TSPAN33). It also found a number of genes with a potential role in lipid related processes, such as SGSM2 and BUB3. The gene CGNL1, whose expression has been shown to change following aspirin intake, was also identified. Additionally, pathway analysis of the networks found enrichment for ALK1 and TGF-beta signalling.

Conclusions:
The study presented here shows how weighted epistatic analysis approaches can complement traditional SNP-by-SNP analyses. Additional studies are necessary to replicate these findings, and they should be applied to other NSAIDs hypersensitivity pathologies. Clin Transl Allergy 2016, 6(Suppl 3):30 Moreover, the mechanisms by which the SNPs and genes identified here affect NSAIDs hypersensitivity must be investigated further. Keywords: NSAIDs-hypersensitivity; GWAS; Genetics; Epistasis; Systems biology Background: Stevens-Johnson syndrome (SJS) is an acute inflammatory vesiculobullous reaction of the skin and mucosa such as the ocular surface, oral cavity, and genitals. In patients with extensive skin detachment and a poor prognosis, the condition is called toxic epidermal necrolysis (TEN). Severe ocular complications (SOC) appear in about 40 % of SJS/TEN patients diagnosed by dermatologists. Among SJS-and TEN patients, especially those with SJS/TEN with SOC, cold medicines (CM) including multi-ingredient cold medications and nonsteroidal anti-inflammatory drugs were the main causative drugs. We reported that in the Japanese, CM-SJS/TEN with SOC was strongly associated with HLA-A*02:06 and significantly associated with HLA-B*44:03; in Indian and Brazilian caucasian populations it was associated with HLA-B*44:03, and in Koreans with HLA-A*02:06. In our 1st genome-wide association study, we analyzed our SJS/TEN with SOC patients using the Affymetrix GeneChip Mapping 500 K array set, and found an association between prostaglandin E receptor 3 (PTGER3) and SJS/TEN with SOC, and subsequently found that this association was stronger in patients with CM-SJS/TEN with SOC than in patients with all SJS/TEN with SOC. In this study, we performed the 2nd genomewide association study using the Japanese CM-SJS/TEN with SOC.

Materials and methods:
We performed a genome-wide association study of Japanese 117 CM-SJS/TEN with SOC patients and 691 controls using the Affymetrix AXIOM Genome-Wide ASI 1 array. For the examination of 17 SNPs in regions near TSHZ2, we genotyped 101 of the patients and 200 of the 691 controls. Results: Manhattan plots showed that the HLA-A region was most strongly associated with the susceptibility for CM-SJS/TEN with SOC. Outside of the HLA region, there were 60 SNPs with a value of p < 10 −3 in either allele frequency, the dominant-, or the recessive model. Among the 11 SNPs of 8 genes with p < 10 −5 , IKZF1 manifested particularly low p values [rs897693 (CC + CT vs TT), OR 5.0, p = 2.1 × 10 −8 ]. Among the 11 SNPs of 8 genes whose value in our second genomewide association study was p < 10 −5 , TSHZ2 also had especially low p values [rs4809905 (AA + AG vs GG), OR 0.3, p = 1.5 × 10 −7 ]. Furthermore, we have examined 17 SNPs in regions near TSHZ2 using 101 CM-SJS/TEN patients and 200 controls, and found that 8 SNPs exhibited a significant genome-wide association with CM-SJS/TEN with SOC. Conclusions: TSHZ2 is one of the susceptibility gene for CM-SJS/TEN with SOC in the Japanese. Background: Dapsone is regarded as the treatment of choice for infections, various dermatological diseases and inflammatory diseases. Drug hypersensitivity syndrome is considered as a severe cutaneous adverse drug reaction which is commonly precipitated by dapsone. A previous publication showed that the HLA-B*13:01 allele is a strong marker for dapsone-induced hypersensitivity syndrome of leprosy patients in China. Although dapsone-induced hypersensitivity reactions is common, however there are no data describing whether HLA-B*13:01 could be used as a genetic marker for prediction of dapsone-induced hypersensitivity reactions in Thai. Objective: The aim of this study was to investigate the predisposition of dapsone-induced DHS, conferred by HLA-B*13:01 in a Thai population. Materials and methods: A total of 22 patients, included 11 patients in dapsone-induced hypersensitivity syndrome, 11 patients in dapsonetolerant control group (dapsone treatment for more than 6 months but without any episode of dapsone-induced hypersensitivity syndrome) and 986 healthy Thai population group. HLA-B genotype were determined by two-stage sequence-specific oligonucleotide probe system (SSOP). This study was approved by the Ethics Committee of Ramathibodi hospital.

Results:
The results presented HLA-B*13:01 allele in patients of dapsone-induced hypersensitivity syndrome, dapsone tolerant controls and healthy Thai population were 63.64 (7/11), 18.18 (2/11) and 13.59 % (134/986) respectively. The HLA-B*13:01 allele were not significantly different between DIHS cases and dapsone tolerant controls (p value 0.0805, OR 7.88, 95 % CI 1.11-56.13), but there were significant different between DIHS cases and healthy Thai population (p value 0.0002, OR 11.13, 95 % CI 3.21-38.52). Background: Some HLA-I alleles are risk factors for the development of severe cutaneous adverse drug reactions (SCARs). HLA-B1502 is strongly associated with the development of Stevens Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) to carbamazepine (CBZ) in Southeast Asian populations where the allele is prevalent. On the other hand, HLA-A3101 has been found to be a risk factor for (CBZ)induced drug reaction with eosinophilia and systemic symptoms (DRESS) in European and Asian patients. HLA-A3101 has been weakly associated to CBZ-induced SJS/TEN in Europeans, and no association has been found with other aromatic antiepileptic drugs (AEDs). No HLA-I alleles have been definitely associated with lamotrigine (LTG)-or phenytoine (PHE)-induced SCARs in Europeans Materials and methods: To explore the association of HLA-I allele frequencies with SCARs to AEDs in our population, 12 patients with DRESS and 14 cases with SJS/TEN included in the Spanish registry PIELenREd were studied. Six cases were related to LTG (3 SJS/TEN; 3 DRESS), 6 were related to CBZ (2 SJS/TEN; 4 DRESS), and 14 cases were induced by PHE (9 SJS/TEN; 5 DRESS). DNA was prepared from total blood and four digits HLA typing was performed. The frequencies of HLA-I alleles in patients with LTG-induced SCARs were compared with frequencies in patients within the other groups, and with previously   Background: HLA class I and class II genotyping has identified patients at risk for both T-cell mediated and IgE/mast cell mediated severe drug hypersensitivity (HSR). Class II HLA-DRA variants have been associated with immediate allergic reactions to beta-lactams and the HLA-DRB1*07:01 allele has been associated with IgE-mediated reactions to asparagine. Up to 27 % of women exposed to 6 or more cycles of carboplatin present with immediate HSR and 50 % of these reactions are anaphylactic. BRCA1/2 mutations have been found to be more common among patients who develop immediate reactions to carboplatin and these reactions, including anaphylaxis, have been successfully addressed by rapid drug desensitization (RDD). We sought to evaluate the HLA profile of patients who presented an initial carboplatin-induced severe hypersensitivity reaction including anaphylaxis, had a positive skin test and were treated with the BWH rapid drug desensitization 3-4 bags protocol. Materials and methods: HLA ABC DR DQ DP typing was conducted for a cohort of Caucasian ovarian cancer patients (n = 11) with a history of grade 2 or 3 type I HSR to carboplatin undergoing RDD and a control group of Caucasian ovarian cancer patients treated with carboplatin, who tolerated 8 or more cycles (n = 12). Allele carriage amongst cases and controls was compared using Fisher's exact test. The Haploblocks program was used to generate cobygram visuals of HLA co-carriage. Results: Among allergic patients, 36 % (4/11) had grade 2 and 64 % (7/11) grade 3 initial HSR. All successfully tolerated the RDD and were able to complete their treatment plans. We found that the HLA-DRB1*15:01 allele was more prevalent among allergic patients (5/11, 45 %) than among the control group (1/12, 8.3 %) (p = 0.06). Cobygram analysis suggests that the HLA class II association may extend to the DQA1*01:02-DQB1*06:02-DRB1*15:01 haplotype (Fig. 6). Conclusions: In this Caucasian cohort of ovarian cancer patients, a specific HLA class II allele, DRB1*15:01, was suggested to be associated with immediate hypersensitivity to carboplatin. Further carboplatin HSR cases and carboplatin tolerant controls are currently been accrued to verify the validity of this association and assess its extension to the DQA1*01:02-DQB1*06:02-DRB1*15:01 haplotype. Background: In case of immediate reactions to beta-lactams, allergological work up consists of detection of specific Immunoglobulin-E (Ig-E) against beta-lactams in serum and skin tests, i.e. prick test and intradermal tests with major and minor antigenic determinants of penicillin, amoxicillin, ampicillin and benzilpenicillin. Levels of specific Ig-E decrease after the reaction and they are no more detectable after some years. It is recommended to perform in vivo and in vitro tests after 3 weeks and no later than 6-12 months after the reaction. Sensitivity of tests then decreases and false negative result may occur. In case of remote history of immediate reaction to beta-lactam, if tests are negative, a provocation test with the culprit drug is necessary and should be followed by repetition of skin tests. Report: We report the case of a woman aged 61 years who experienced a systemic reaction (urticaria, vomit, diarrhea, fatigue) 15 min after intake of amoxicillin/clavulanic acid. Four months later, she underwent a visit in our Allergy Unit and serological and skin tests were scheduled. Serological specific Ig-E against penicilloyl G, penicilloyl V, ampicillin, amoxicillin, cefaclor as well as skin tests gave negative result. They were performed respectively 5 and 9 months after the reaction. A drug provocation test (DPT) with amoxicillin was then performed and was considered positive for the occurrence of generalized pruritus 20 min after the intake of the last dose (cumulative dose 875 mg). Skin tests were repeated with positive results to both amoxicillin and ampicillin, at the concentration of 1 and 20 mg/ml, respectively. How this report contributes to current knowledge: Specific Ig-E levels against beta-lactams decrease after immediate-type reactions. Guidelines recommend to perform allergological work up within 6-12 months. Our case shows how this period might be too long and false negative tests can occur even if performed within one year. DPT should always follow negative skin tests to obtain a correct diagnosis. Background: There are no good epidemiological data regarding opioid allergy (OA). Many side effects can occur with this group of drugs. These are often misinterpreted as an IgE-mediated OA. As a consequence, many patients receive an unsubstantiated diagnosis of OA and avoid opioid unnecessarily. Diagnosis of OA can be challenging as skin tests (ST) and opioid-specific IgE have a poor predictive value. Drug provocation tests (DPT) remain the gold standard for the diagnosis of OA. However, there are almost no studies of opioid DPT and no validated opioid DPT protocols. Materials and methods: 30 suspected cases of OA (12 morphine, 18 codeine) were studied using detailed history and oral DPT. Opioid ST and specific IgE were not performed. Standardised local protocols were used. For morphine: 2, 3, and 5 mg morphine sulphate oral solution (10 mg/5 ml) was administered at 30 min interval with 120 min monitoring. For codeine: 10, 20 and 30 mg codeine phosphate syrup (25 mg/5 ml) was administered at 30 min interval with 60 min of monitoring. All DPT were performed on a specialist allergy unit. Results: 25 females and 5 males (median age of 46.5) experienced various symptoms reported as OA. Opioids were prescribed mainly for analgesia. 20 patients (67 %) had cutaneous symptoms: angioedema: 5, urticaria: 4, angioedema and urticaria: 2, unspecified rash: 5, angioedema, unspecified rash and pruritus: 3, angioedema and unspecified rash: one. 11 patients (37 %) experienced symptoms suggestive of anaphylaxis: dyspnoea, tachycardia, hypotension, dizziness and collapse. 2 of these (18 %) experienced cutaneous symptoms too. Other non-specific symptoms included nausea: 2, paraesthesia: 2, tremor: 1, anxiety: 1. DPT were negative in 23 patients (77 %). 6 patients (20 %) had symptoms of intolerance: pruritus, nausea, dizziness, tremor to morphine (2) and codeine (4). Only 3 % of DPT were positive: 1 patient experienced angioedema with codeine. Conclusions: DPT-confirmed OA appears to be very rare (3 %). Most symptoms misinterpreted as OA could be due to a dose-dependent mast cell degranulation, genetic polymorphism of CYP2D6 gene or the underlying acute illness. Morphine and codeine DPT are a safe and reliable diagnostic tool. Our ongoing multi-centre study will endeavour to validate this approach in a larger cohort of suspected OA patients (including other opioids) and produce standardised DPT protocols to improve the diagnosis of OA in Europe and worldwide. Background: Specific IgE against β-lactams by CAP FEIA system (Thermo Scientific ® ) used to use the cut-off of 0.35 kU/l, but now we can get a detection limit of the assay of 0.10 kU/l. We pretend to evaluate if this change of cut-off from 0.35 to 0.10 kU/l improves the sensitivity without compromise its specificity. Materials and methods: 74 patients older than 18 years evaluated in the allergy outpatient clinic since January 2011 to April 2014 were studied. They were classified as allergic by history and skin tests positive to β-lactamic antibiotics. Specific IgE against penicilloyl G, penicilloyl V, amoxicilloyl and ampicilloyl were analyzed by CAP FEIA system (Thermo Scientific ® ). With these IgE values and positive or negative diagnosis of allergy, sensitivity and specificity of both cutoffs (0.35 and 0.10 kU/l), the ROC curves were obtained. In addition, the AUC value (with their confidence interval) was calculated. The SPSS (v19.0) and "Analyse-it"-Excel were used. Results: Tables 5, 6, 7. Conclusions: The cut-off of 0.10 kU/l may be more appropriate to use in the clinical practice because it improves the correct classification of b-lactams allergy patients. The amoxicilloyl obtains the best performance with this new cut-off. Background: The time of determination of specific IgE (sIgE) to potential culprit drugs, as an aid in the diagnosis of peri-operative anaphylaxis, is not well defined for all drugs. Report: A 62-year old man experienced an anaphylaxis within 15 min after receiving a gelatin-containing plasma expander during general anesthesia for hip surgery after a high velocity trauma. Decontamination was performed with chlorhexidine, and propofol, lidocaine, sufentanil, rocuronium, dexamethasone, was adminstered 2h15 and cephazolin 1h45 prior to the event. The gelatin infusion was stopped and treatment with epinephrine, norepinephrine, promethazine, hydrocortisone, and saline fluid expansion installed. Serum tryptase   was transiently increased (95.7 ng/dl 1h30 after the onset of the reaction vs 6.0 ng/dl > 24 h after the event). ImmunoCAP sIgE (Thermofisher-Phadia, Sweden) to gelatin, galactose-alpha-1,3-galactose, ethylene oxide, latex, and chlorhexidine was negative on the sample obtained 1h30 after the event, and independently confirmed. However, repeat sampling 16 days after the event with a serial dilution of the gelatin-containing plasma expander, mimicking the timing of the initial testing, demonstrated the inhibition of sIgE determination with a 50 % inhibitory concentration (IC50) of 0.02 %. No serum before the anaphylaxis was available to confirm a pre-existing sensitization. Skin testing 4 weeks after the event was positive for the 4 % gelatin-containing plasma expander (3 and 5 mm wheal diameter after skin prick testing at a 1:10 and 1:1 dilution respectively) and negative for chlorhexidine, latex, and cephazoline. How this report contributes to current knowledge: A rare case of IgEmediated gelatin allergy is reported. We hypothesized that the initial sIgE for gelatin was false negative due to competition of infused gelatin with the gelatin-immunoCAP assay rather than a boostin phenomenon had taken place, suggesting careful interpretation of sIgE determinations very early after the event, at least in the case of gelatin-sIgE. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images.  ) and benzylpenicillin (penicillin G) and Semi-synthetic penicillins (amoxicillin, amoxicilin/clavulanic acid and ampicillin) were also systematically tested, as well as any other suspected beta-lactam.
In the case of negative results, we perform provocation tests with the suspected drug. Considering the temporal variation for immediate reactions in terms of skin test positivity, Patients were classified according to the year they referred the reaction, in four periods (>1980, 1980-1990, 1991-2000 and >2001-2009) Results: From a total of 2716 patients initially evaluaed, 296 were finale confirmed as inmediate reactions to Betalactamic. A total of 247 were diagnosed by skin testing, this represents 83 % of total (247/296). Considering the temporal variation for immediate reactions in terms of skin test positivity, the analysis of the AX determinants showed that there was a gradual increase over the years that varied from 38.5 to 81.2 %. Statistical analysis confirm a strong signification p < 0.0001. In parallel a decreased of antigenic determinants of penicillin (including PPL, MDM and Benzylpenicillin) from 30.8 to 12.7 % also statistic significance p < 0.007. Conclusions: Our study confirm that the variation of beta-lactam pattern consumption modify the skin test response in a long series over 10 years. Background: ln order to emulate the recognition process working in vivo, much effort have been made to prepare hapten(drug)carrier(protein) conjugates attempting to work like the antigen responsible for the allergic drug reaction.

Materials and methods:
In our efforts to exploit the dendrimer properties in the interaction with the immunological system, we have prepared a series of Dendrimeric:Antigens (DeAn), to study the dendritic cell (DC) maturation as a test to detect allergy reactions to amoxicillin. Recently our research group developed a new kind of dendrimer, called BAPAD, that we have used in this work to obtain the dendrimeric moiety of the target molecule. To this avail we synthesized a generation two BAPAD dendrimer using cystamine as core. Then, the free amine groups on the surface of the dendrimer were functionalized with an amoxiciloyl group (AXO). The fluorescent DeAn has been fully characterized by NMR and MS techniques, and their fluorescent properties well established in aqueous biological media using confocal microscopy. The fluorescent dendron (De) without the haptenic moieties at the periphery has been also obtained and fully characterized as a control assay. The fluorescent DeAn and De was used in dissolution and supported in solid surface (cellulose disk). The solid conjugates were immunologically evaluated by RAST inhibition using sera from 7 patients allergic to amoxicillin. DC from four amoxicillin allergic patients have been incubated with fluorescent DeAn and De and studied with a flow cytometer to determine whether or not the cells were able to uptake both compounds. Results: Flow cytometry and confocal microscopy show that these dendrimeric structures interact with DC and are internalized by them to the cellular cytoplasm. The maturation of DC was tracked by by flow cytometry. In all cases, low maturation induced by DeAn in allergic patients is observed. This effect can be due to two factors: (1) that the concentration of compound that enters the DC is low and (2)   are implicated remains problematic. We describe a case of toxic epidermal necrolysis (TEN) in the setting of multiple implicated antimicrobials and the utility of T-cell enzyme linked immunospot assay (ELISpot) to define antimicrobial causality. Report: A 20-year old man was admitted to a tertiary referral trauma centre for management of wound sepsis and femoral stump osteomyelitis in the setting of recent below-knee amputation following a highspeed motorbike accident. Whilst receiving escalating antimicrobial treatment, for bacteraemia and fevers >38.3 °C, he developed a blistering rash involving >30 % of body surface area (BSA) associated with a positive Nikolsky sign, consistent with TEN. Multiple antimicrobials were administered prior to onset of TEN, four of which-vancomycin, meropenem, linezolid and teicoplanin-were temporally associated with the onset of TEN. How this report contributes to current knowledge: We sought to use cellular assays, IFN-γ ELISpot and flow cytometry, to identify the causative agent of TEN in a patient receiving multiple antibiotics. Following informed consent, patient whole blood was collected on day 4 post onset of TEN. PBMCs were extracted and cryopreserved. HLA ABC DR DQ DP typing was performed and the PBMCs were used for ex vivo ELISpot testing. PBMCs were also incubated with candidate drugs for 18-20 h at 37 °C in 5 % CO 2  We believe this to be the first reported use of T-cell ELISpot to assign isolated teicoplanin causality to TEN. Consent: Written informed consent was obtained from the patient for publication of this abstract and any accompanying images. , is used to identify the culprit drug in cases of cutaneous adverse drug reactions (cADR). While DLST is widely used as in vitro diagnostic tool, its sensitivity and specificity are unsatisfactory. Determination of antigen-specific IFN-γ production by enzyme-linked immunospot assay (conventional IFNγ-ELISpot) is well-established diagnostic method for tuberculosis infection, and recent reports suggested that drug-induced conventional IFNγ-ELISpot is useful for identifying the culprit drug of cADR cases. The aim of this study was to establish a novel diagnostic method for identifying the culprit drug in cADR patients through the efficient detection of the drug-specific IFN-γ production by IFNγ-ELISpot. Materials and methods: Ten cases of cADR caused by clinically convincing culprit drugs were enrolled in this study. Peripheral blood mononuclear cells (PBMCs) from all 10 patients were used for both DLST and drug-induced conventional IFNγ-ELISpot. In addition, druginduced IFNγ-ELISpot was also performed by using PBMCs which were non-specifically stimulated with monoclonal antibodies for 7 days before exposing culprit drugs (modified IFNγ-ELISpot) in all cases. Results: Drug-induced IFN-γ production was detected by modified IFNγ-ELISpot in 5 patients of which DLST and conventional IFNγ-ELISpot were both negative. Moreover, IFN-γ secretion was observed by modified IFNγ-ELISpot in all 4 patients of which DLST were positive. Conclusions: Modified IFNγ-ELISpot using expanded PBMCs is more sensitive than conventional IFNγ-ELISpot for detecting drug-induced IFN-γ production. Therefore, this novel IFNγ-ELISpot could be a useful in vitro tool for identifying culprit drugs in cADR cases. Patch test and lymphocyte stimulation test (LST; also known as DLST in Japan) are frequently used for this purpose, but their positivity ratios are not sufficiently high. We sought to explore a novel method using skin-infiltrating T cells for determination of causative drugs because it is considered that antigen-specific T cells infiltrate in skin lesions of the severe drug eruptions and participate in its pathogenesis.

Materials and methods:
We expanded skin-infiltrating T cells from 4-mm biopsied lesional skin samples of severe drug eruption using anti-CD3/CD28 antibodies and IL-2. More than 10 7 T cells/specimen were obtained by 2-week cultivation. To investigate their cytokine production by in vitro stimulation with causative drugs, the expanded T cells were co-cultured with drugs peripheral blood mononuclear cells (PBMCs) from the same patient, and IFN-g production was assessed by ELISpot assay. Moreover, to see the drug-induced T-cell proliferation, the expanded T cells were labeled with CFSE and cultured with drugs and X-ray-irradiated PBMCs for a week, and the proliferation was assessed by flow cytometry. The cytokine profile of the cells which proliferated in response to drugs was also assessed by flow cytometry.

Results:
The ELISpot assay showed a significantly high number of T cells produced IFN-g by drug stimulation as compared to no addition control. The CFSE assay revealed that both CD8+ and CD4+ T cells proliferated in response to causative drugs in SJS/TEN and DIHS/ DRESS. Notably, the majority of CD8+ T cells proliferating to causative drugs expressed IFN-g in SJS/TEN.

Conclusions:
Our study suggests that the use of ex vivo expanded skin-infiltrating T cells can yield a novel method for determination of causative drugs in the severe drug eruptions. Keywords: T cells; IFN-γ

Materials and methods:
The aim of this study was to use the β-lactam antibiotic piperacillin as a paradigm to fully characterise the phenotype and function of drug-specific T cells. T cells were cloned from both blood and inflamed skin of hypersensitive patients and naïve T cells from healthy donors were primed to piperacillin using dendritic cells.
Results: Drug-specific clones were generated from both blood (n = 570, 84 % CD4) and skin (n = 96, 83 % CD4) from patients hypersensitive to piperacillin. All clones secreted high levels of IFNγ and IL13 following drug stimulation. Interleukin-22, perforin and granzyme B were also secreted by over 50 % of clones. In contrast, IL17A secretion was not detected. Naïve T cells primed to piperacillin using autologous dendritic cells, proliferated in the presence of drug (p = 0.001, SI > 2) and had a similar pattern of cytokine secretion to clones generated from hypersensitive patients. Significant differences in chemokine receptor expression were observed between the different populations of T cell clones. CLA, CXCR6 and CCR1 expression was higher on piperacillin-specific skin-derived clones when compared to non piperacillin-specific skin-derived clones (p = 0.01). CCR2, CCR4, CXCR1 and E-cadherin were higher on skin-specific clones when compared to blood-specific clones (p = 0.01). Piperacillin-specific clones isolated from blood and skin of hypersensitive patients, as well as piperacillin-specific T cells from healthy donors migrated in the presence of chemokines specific to their respective cell surface receptors, with migration to CCR4 and CCR10 most prevalent. Finally, regulation of the cytokine secretion through modulation of nuclear receptor signalling was studied. Inhibition of the aryl hydrocarbon receptor during naïve T cell priming abrogated the drug-specific cytokine response. Conclusions: Our data describe a subset of piperacillin-specific T-cells that secrete IL-22, IFNγ, perforin and granzyme B, but not IL-17, in response to antigen challenge. Taken together this suggests that IL-22 is important in the progression of β-lactam hypersensitivity. Background: Glycopeptide antibiotics, vancomycin and teicoplanin, share a similar structure and are the mainstay of therapy for severe gram-positive organisms. Hypersensitivity responses to vancomycin are well recognised but the risk of cross-reactivity with teicoplanin is unclear. Our study aims to examine the role of T cell responses in vancomycin hypersensitivity reactions and explore the potential for crossreactivity between vancomycin and teicoplanin. Materials and methods: Our cohort comprised of vancomycin exposed allergics who had suffered delayed skin drug hypersensitivity reactions n = 17; non-allergic previously vancomycin exposed controls n = 5; and vancomycin naïve controls n = 12. We tested ex vivo drug induced lymphocyte proliferation and cytokine release. Vancomycinspecific T cell lines were grown to test for teicoplanin cross-reactivity. Results: In our cohort of vancomycin allergics, vancomycin hypersensitivity reaction patterns were drug exanthems (47.1 %), DRESS (29.4 %), or SJS/TEN (23.5 %). Circulating IFN-γ vancomycin-specific T cells were identified at higher frequency than naïve controls: (IFN-γ p < 0.0001; SI p = 0.042). Interestingly, detectable frequencies in vancomycin exposed controls were higher than naïve controls (p < 0.0001; SI p = 0.12) suggesting that low frequency responses were the result of vancomycin priming even in the context of a non-allergic individual. This was confirmed by the expansion of short term T cell lines in vancomycin exposed controls (IFN-γ p = 0.008; SI p = 0.016). Crossreactivity against teicoplanin was found to be minimal (42.7 × 10 −4 % IFN-γ and SI 1.0 in vancomycin-specific T-cell lines compared to 48 × 10 −4 % IFN-γ and SI 1.3 in non-vancomycin-specific T-cells lines). Conclusions: Circulating vancomycin specific-T cell frequencies were found to be higher in vancomycin allergics than vancomycin exposed controls, which in turn were higher than naïve controls. Using vancomycin-specific T cell lines we did not see any evidence of teicoplanin cross-reactivity despite the similar molecular structures of the two drugs. We also showed that low-level of vancomycin-specific responses identified ex vivo in exposed controls were able to efficiently expand on short term culture, confirming that they were genuine vancomycin-specific T cells. This suggests both immune predisposition and potentially adaptive regulation may be important in regulating the development of hypersensitivity reactions to vancomycin. Keywords: Drug hypersensitivity reactions; T cell; Vancomycin; In-vitro diagnostic tests Background: The mechanism of drug desensitization is scarcely understood. The aim of the study is to observe the cytokine levels in the serum of patients who underwent a successful drug desensitization.

Materials and methods:
Patients with a hypersensitivity reaction to any culprit drug and therefore has to be desensitized with the drug were included into the study. IL-4, IL-5, IFN γ and IL-10 levels were determined with ELISA in the peripheral serum samples of the patients before the desensitization to any culprit drug and within 24 h after the procedure. The results were compared with the serum samples of patients who could tolerate the same drugs and healthy subjects who were not exposed to these drugs. Results: 26 patients who experienced allergic reactions due to various drugs and therefore had to be desensitized, 10 patients who could tolerate the same drugs and 5 healthy subjects were included. The diagnosis of the patients were as follows: malignancy (14 patients), multiple sclerosis (2 patients), metabolic storage disorders (2 patients), iron salt deficiency (2 patients) and Basedow Graves disease (1 patient), coronary heart disease (1 patient), and congenital adrenal hyperplasia (1 patient). The drugs used for desensitization in the order of the most frequent to the least were as follows: parenteral or per oral chemotherapeutics, aspirin, corticosteroids, storage enzymes, iron salts and anti-thyroidal drugs. Skin prick tests were positive in 5 patients with parenteral chemotherapeutics, 2 patients with iron salts, 2 patients with storage enzymes and in one patient with methylprednisolone. The baseline cytokine levels were not statistically different between the three groups. The desensitization was not successful in 4 of the patients and because of this insufficient patient number their cytokine levels were not further analyzed. The IL-10 levels after the successful desensitization procedure in 22 patients significantly increased when compared to their baseline levels (p: 0.006). The rise in IL-10 levels were greater in chemotherapeutic desensitizations than the desensitizations with other drugs (p: 0.005) whereas the other three cytokines did not significantly change.
Conclusions: Successful desensitization can be related with increase in IL-10. In order to further elucidate the mechanism of successful desensitization, cells secreting IL-10 should be examined. Keywords: IL-10; Desensitization Background: Fluoroquinolones (FQ) are the second most frequent cause of hypersensitivity to antibiotics after betalactams. Most reactions induced by FQ were immediate. For the in vitro diagnosis only the basophil activation test (BAT) has shown to be useful although with suboptimal sensitivity. The aim of our study was to analyze the BAT to FQ using two different activations markers, CD63 and CD203c, in the evaluation of patients with immediate allergic reactions to these drugs. Materials and methods: Seventeen patients with confirmed immediate allergic reactions to FQ (6 to Ciprofloxacin and 11 to Moxifloxacin) were included in the study. Eighteen controls with tolerance to FQ were also included. BAT was performed with Moxifloxacin and Ciprofloxacin at 2 and 0.2 mg/ml using CD203c and CD63 as activation markers. Positive results were considered when SI > 3 to at least one of the concentrations used in the test. Results: Data indicated that although both Ciprofloxacin and Moxifloxacin are able to induce both activation marker expression (CD63 and CD203c), there is a predominance in the expression of each one depending on the drug included in the test. Thus Ciprofloxacin was able to mainly increase the expression of CD63 (40 %, p = 0.0053) whereas Moxifloxacin mainly increase the expression of CD203c (10 %). In addition, analyzing the expression of both markers in basophils from Moxifloxacin allergic patients stimulated with the culprit drug, we found a higher expression of CD203c in patients suffering anaphylactic shock (7 %), whereas was CD63 the marker that showed a higher up-regulation in patients with anaphylaxis (17 %). When we analyzed the sensitivity and specificity of the test using these activation markers we can see that the best results were observed using the culprit drug and CD203c as activation marker for Moxifloxacin (S = 36.4 % and E = 94.4 %) and CD63 for Ciprofloxacin (S = 83.3 % and E = 88.9 %).

Conclusions:
The BAT must be performed using the culprit drug and CD203c for Moxifloxacin or CD63 for Ciprofloxacin as activation marker to diagnose Quinolone Allergy. Although this differential expression of both activation markers seems to be also related with the culprit drug and clinical entity. Using this criteria and a cut-off of 3, we have obtained a better sensitivity for Ciprofloxacin.

P172
The Background: Celecoxib, is a specific COX-2 inhibitor which is an alternative treatment for patients with intolerance to NSAIDs. Report: We present two cases of anaphylaxis due to Celecoxib. The first is a 57 year old male who was taking Celecoxib as an alternative medication for sciatic pain since he had poor gastric tolerance with NSAIDs. He had a history of idiopathic recurrent urticaria. He had an episode of anaphylactic shock 30 min after taking 1 tablet of Celecoxib which prompted him to sought consult at the emergency room wherein he was administered with Epinephrine IM. On follow up after 1 month, prick test with Celecoxib revealed negative. Because the suspicion that the reaction was caused by allergy to Anisakis, a challenge test with Celecoxib was done that resulted positive, and epinephrine was administered. Basophil activation test was positive with Celecoxib and negative to Parecoxib. Two months later, he presented with hives 2 h after taking 750 mg of acetylsalicylic acid (ASA). Tolerance test with Meloxicam and Nabumetone were performed which the patient tolerated well. The second case is a 58 year old male who had an episode of anaphylaxis 3 h after taking Celecoxib for headache. Tryptase was elevated, 19.9 μg/l. A month earlier, he had generalized itching after taking one tablet of celecoxib. He took Metamizol previously which he tolerated well. No history of atopy nor allergy to medications. Skin tests to NSAIDs were negative. Basophil activation test was positive with celecoxib and negative to ASA, Metamizole, Paracetamol, Parecoxib and Dexketoprofen. He underwent challenge test with Aspirin with positive result. Both patients were diagnosed with intolerance to NSAIDs and anaphylaxis secondary to Celecoxib.
Background: Basophil activation test (BAT) is reported to be a useful and very promising technique in the diagnosis of immediate type drug hypersensitivity reactions. It is used in combination with in vivo and in vitro diagnostic tools and may contribute to the sensitivity of the diagnostic work out.

Materials and methods:
In order to investigate the role of BAT in the diagnosis of immediate type drug hypersensitivity to betalactam antibiotics we analyzed all BATs performed with betalactam antibiotics in our department during the period from 2009 to 2012. We compared the results of in vivo diagnostics (skin prick test, intracutaneous test, patch test) and in vitro diagnostics (specific IgE) with the results of the BAT under the aspect, if BAT represent a useful tool for assessment of the individual risk of the patient to experience another immediate type drug hypersensitivity reaction on reexposure to the tested drug. Results: We performed BAT with betalactam antibiotics in 64 cases: 20 % (n = 13) with penicillin (PEN), 38 % (n = 24) with aminopenicilins (AMP) and 42 % (n = 27) with cephalosporins (CPH).
In the PEN-group 23 % (n = 3) of the patients had at least one positive in vivo test, but negative BAT and 15 % (n = 2) had positive BAT, but negative in vivo tests.
In the AMP-group 17 % (n = 4) of patients had at least one positive in vivo test, but negative BAT and 17 % (n = 4) had positive BAT, but negative in vivo tests. Only 8 % (n = 2) of patients had positive both BAT und at least one in vivo test. 4 % (n = 1) of patients had both positive at least one in vivo test and specific IgE, but negative BAT.
In the CPH-group 22 % (n = 6) of the patients had positive BAT, but no other positive test results and 4 % (n = 1) had positive both BAT und at least one in vivo test.

Conclusions:
In case of the negative in vivo and in vitro test results (inclusive BAT) the individual risk of the patient to experience another immediate type drug hypersensitivity reaction on reexposure to the tested drug was considered to be low, so drug provocation test (DPT) as the next diagnostic step was recommended: from overall of 41 such cases DPT was performed in 32 % (n = 13) and was unremarkable in 100 % (n = 13).
Our results confirm that BAT may be an important tool to increase the sensitivity of the diagnostic and make the better risk assessment possible. However, the limitation of this study is that we didn't perform DPT in patients with positive in vivo or in vitro results and therefore are not able to estimate the frequency of false positive BATs. Frequency of positive in vivo and in vitro results in the diagnostic work out of immediate type drug hypersensitivity reactions to betalactam antibiotics in Department of Dermatology and Allergology at the University Hospital of Aachen, Germany during the period from 2009 to 2012. Positive BAT results in patients with negative in vivo tests and specific IgE may provide important information for assessment of the individual risk of the patient to experience another immediate type drug hypersensitivity reaction on reexposure to the tested drug (Table 10) Background: The factors governing inter-individual susceptibility to drug hypersensitivity remain ill-defined. Although the association of specific HLA alleles with hypersensitivity is important, for most drugs, the majority of individuals who are positive for an HLA risk allele do not develop a reaction. Thus, predisposition is likely mediated by other parameters, which may include T-cell co-inhibitory pathways. As polymorphisms in co-inhibitory pathways are associated with dysregulated immune responses, we investigated the role of these pathways during drug (SMX-NO)-specific T-cell responses. Programmed death-1 (PD-1) and cytotoxic T-lymphocyte associated protein 4 (CTLA4) are considered to be key immune checkpoints, and TIM-3 is of current interest due to its reported upregulation alongside PD-1.

Materials and methods:
Naïve and memory T-cells from healthy donors were incubated for 8 days with SMX-NO and dendritic cells ± PD-L1, CTLA4, TIM-3 blocking antibody. Antigen-reactivity was then assessed by T-cell cytokine secretion and proliferation. Cell phenotype was assessed by flow cytometry. T-cell clones were then generated from these cultures. Results: While blockade of PD-L1 or CTLA4 enhanced the activation of SMX-NO-primed naïve T-cells, only the blockade of CTLA4 enhanced the proliferative response of antigen-stimulated memory T-cells suggesting a greater regulatory role for CTLA4 during secondary T-cell responses. Blockade of TIM-3 had no effect on T-cell activation of either naïve or memory cells. While all receptors were upregulated on T-cells after antigen exposure, PD-1 was upregulated at earlier time points than CTLA4 and TIM-3 indicating a differential role for these receptors during early and late stage T-cell activation. High expression of individual co-inhibitory receptors has previously been associated with exhausted T-cells, while other studies indicate that these cells are highly functional. We found no correlation between the level of