From: Fungal allergy in asthma–state of the art and research needs
Entity | Current definition | Proposed definition | Comments |
---|---|---|---|
Fungal allergy | Immune-mediated inflammatory response to a fungus sometimes leading to tissue damage | Same, being inclusive of all allergic immunopathologies | Demonstrating and documenting ‘Tissue damage’ can sometimes be difficult. |
Fungal sensitisation | Immune-mediated response to a fungus, without evidence of inflammation or tissue damage, usually documented by an elevated fungal-specific IgE. | Same | Tends to reflect specific-IgE response (or skin prick test result) only. |
Fungal colonisation | None | 1. One (or preferably two or more) respiratory sample (s) positive for a fungus by culture or PCR | Such criteria may apply to other filamentous fungi, but not Candida. They need to be tested in prospective studies. |
2. No new major respiratory symptoms | |||
3. No evidence of ABPA or other forms of aspergillosis | |||
4. No overt immunocompromise | |||
5. Negative fungal specific IgG in serum. | |||
ABPA | 1. Asthma (or CF) with deterioration of lung function | 1. Asthma (or CF) | No definition addressed robustly with prospective study and combinations of diagnostic criteria. |
2. Elevated total serum IgE of >1000 ng/ml (>417 IU/ml) | 2. A. fumigatus skin test positive or elevated A. fumigatus IgE levels | ||
3. Elevated A. fumigatus specific IgE and/or IgG antibodies | 3. Elevated total serum IgE of >1000 IU/ml | ||
+ 2 of the following: | |||
a. Positive A. fumigatus IgG or precipitating antibodies | |||
b. Radiographic opacities consistent with ABPA | |||
c. Eosinophil count >500 cells/uL | |||
4. Immediate Aspergillus species skin test reactivity | |||
5. Eosinophilia (>1,000/uL) | |||
6. Presence of central (or proximal) bronchiectasis | |||
7. Chest radiographic infiltrates | |||
8. High attenuation mucus present. | |||
Allergic bronchopulmonary mycosis (ABPM) | 1. Asthma (or CF) with deterioration of lung function | No new proposal, but similar to ABPA, with substitution of a different fungal specific tests. | Too rare to develop patient cohorts to formally validate a definition. |
2. Elevated total serum IgE of >1000 ng/ml (>417 IU/ml) | |||
3. Elevated fungal specific IgE and/or IgG antibodies | |||
4. Immediate fungal species skin test reactivity | |||
5. Eosinophilia (>1,000/uL) | |||
6. Presence of central (or proximal) bronchiectasis | |||
7. Chest radiographic infiltrates | |||
Severe asthma with fungal sensitisation (SAFS) | 1. Severe asthma | Severe asthma is a variable, usually treatment-based entity. | |
2. Total IgE <1,000 IU/mL | Variable performance of different skin and sIgE test reagents, makes SAFS an imprecise entity until diagnostics improve. | ||
3. Sensitisation to any fungus by skin prick test or sIgE | |||
Aspergillus bronchitis | None | 1. Multiple respiratory sample positive for Aspergillus spp by culture or PCR | Few patients reported. Some cases are caused by non-fumigatus species, and so serology criterion may be falsely negative. |
2. Major respiratory symptoms for >4 weeks | |||
3. No evidence of ABPA or other forms of aspergillosis | |||
4. No overt immunocompromise | |||
5. Positive Aspergillus IgG or precipitins in serum. |