Acute generalized exanthematous pustulosis.

The key clinical features of acute generalized exanthematous pustulosis (AGEP) are the acute occurrence of numerous pinhead-sized nonfollicular sterile pustules on an edematous erythema accompanied by fever and leukocytosis. Histology shows mainly spongiform subcorneal and/or intraepidermal pustules, frequently a marked edema of the papillary dermis, neutrophils, and often eosinophils. AGEP is a reaction pattern mostly caused by drugs, the ones with the highest risk being antibacterial agents like ampicillin/amoxicillin, and quinolones, pristinamycin, anti-infective sulfonamides, the antimycotic drug terbinafine, (hydroxy)chloroquine, and diltiazem. In addition, a large number of other drugs as well as infections have been reported as triggers. AGEP is an acute and sometimes severe reaction. When the causative agent is withdrawn, it usually resolves quickly without specific treatment.