Table 1 Classification of DHR according to Gell and Coombs and adapted by Pichler et al. [4]
Type | Type of immune response | Pathophysiology | Clinical symptoms | Typical chronology of the reaction |
|---|---|---|---|---|
I | IgE | Mast cell and basophil degranulation | Anaphylactic shock, Angio-oedema, Urticaria, Bronchospasm | Within 1–6 h after the last intake of the drug |
II | IgG and complement | IgG and complement-dependent cytotoxicity | Cytopenia | 5–15 days after the start of the eliciting drug |
III | IgM or IgG and complement or FcR | Deposition of immune complexes | Serum sickness, urticaria, vasculitis | 7–8 days for serum sickness/urticaria 7–21 days after the start of the eliciting drug for vasculitis |
IVa | Th1 (IFNγ) | Monocytic inflammation | Eczema | 1–21 days after the start of the eliciting drug |
IVb | Th2 (IL-4 and IL-5) | Eosinophilic inflammation | MPE, DRESS | 1 to several days after the start of the eliciting drug for MPE 2–6 weeks after the start of the eliciting drug for DRESS |
IVc | Cytotoxic T-cells (perforin, granzyme B, FasL) | Keratinocyte death mediated by CD4 or CD8 | FDE, MPE, SJS/TEN, Pustular exanthema | 1–2 days after the start of the eliciting drug for fixed drug eruption 4–28 days after the start of the eliciting drug for SJS/TEN |
IVd | T-cells (IL-8/CXCL8) | Neutrophilic inflammation | AGEP | Typically 1–2 days after the start of the eliciting drug (but could be longer) |