Multilocular fixed drug reaction mistaken for intertrigo in a diabetic

History and clinical findings: A 57-year-old man with diabetes and hyperten sion was treated with amoxycillin, clarithromycin and pantoprazole fora gas tric ulcer positive for Helicobacter pylori. On the second treatment day he developed inguinal pruritus with erythema. He presented at out-patient cli nic on the 5th day suspected of having Candida intertrigo. He had bright re d, relatively well-circumscribed erythema, most marked at the edges, mainly over the inguinal region and the inside of the thigh. There were no other symptoms. Investigations and diagnosis: Bacteriological and mycological tests of the affected skin were unremarkable. Immunological tests showed a normal total IgE but were negative in the CAP-FEIA test for penicilloyl G, penicilloyl V , amoxycilloyl and ampicilloyl. An epifocal epicutaneous test with amoxycil lin and ampicillin (5% each in vaseline and doritin) gave a ++ positive rea ction and confirmed a suspected fixed drug reaction. Treatment and course: After amoxycillin had been discontinued and local cla ss III steroids had been administered (mometasone furoate, Ecural(R)) for o ne week the cutaneous changes disappeared without complication, except for slight hyperpigmentation. H. pylori eradication was continued without furth er complications using clarithromycin, metronidazole and pantoprazole. The patient was issued with an "allergic to penicillin" card. Conclusion: Intertriginous changes during antibiotic treatment may not be d ue to Candida intertrigo, which is fairly common, but to a prognostically m uch more important drug reaction.