Roujeau et al reported criteria for the diagnosis of acute generalized exanthematous pustulosis (AGEP). The authors are from the University of Creteil in France.
Criteria - all of the following:
(1) widespread edematous erythema with numerous, small, mostly non-follicular pustules
(2) histopathologic findings (below)
(3) fever > 38°C
(4) absolute neutrophil count > 7 * 10^9/L
(5) acute evolution with spontaneous resolution of pustules within 15 days
Histopathologic findings - both of the following:
(1) intra-epidermal or subcorneal pustules
(2) dermal edema, vasculitis, perivascular eosinophils and/or focal necrosis of keratinocytes
The time to onset after exposure to an implicated drug was often less than 24 hours