Table 1.

Most common associations with erythema multiforme

1. Micro-organisms

Viruses: herpes viruses (HSV, VZV, EBV), adenoviruses, enteroviruses, hepatitis viruses (A, B and C), HIV, influenza

Bacteria: Mycoplasma pneumoniae, Chlamydia, Corynebacterium diphtheria, Hemolytic streptococci, Legionellosis

Fungi and parasites: coccidioidomycosis, dermatophytes, histoplasmosis, sporotrichosis

2. Drugs: allopurinol, barbiturates, cancer chemotherapeutic agents, carbamazepine, cephalosporins, non-steroidal anti-inflammatory drugs, penicillins, phenytoin, protease inhibitors

3. Food additives or chemicals: benzoates, nitrobenzene, terpenes, ethanol

4. Immune and other conditions: graft versus host disease, immunisation (BCG, hepatitis B), inflammatory bowel disease, pregnancy, sarcoidosis, systemic lupus erythematous