Acute generalized exanthematous pustulosis resembling toxic epidermal necrolysis caused by famotidine.

A morbidly obese 60-year-old Hispanic woman with chronic obstructive pulmonary disease, renal failure and asthma but no history of skin disease was hospitalized for a putative urinary tract infection. She had developed a red pruritic painless rash 2 days after starting famotidine. She was allergic to ampicillin and had taken dexamethasone, prozac, percocet, diltiazem, theophylline, ciprofloxacin and albuterol in the preceding month’s hospitalization. Examination revealed diffuse erythema, a positive Nikolsky’s sign and erosions on her torso (Fig. 1) and fragile 2 – 3 mm pustules over her chin, neck and forearms (Fig. 2). Her palms, soles and mucous membranes were clear. Blood analysis revealed leucocytosis (30,600/cc), neutrophilia (95.6%) and few eosinophils (0.3%). Liver enzymes and screening for lues (RPR) were normal. Bacterial culture of blood and urine grew no organisms. Bacterial cultures of eroded neck skin grew Staphylococcus epidermidis. Both frozen sections and haematoxylin and eosin biopsies revealed subcorneal blistering, devoid of necrolytic keratinocytes, acantholysis, spongiosis and organisms, findings consistent with AGEP rather than TEN, pustular psoriasis or staphylococcal scalded skin syndrome. Famotidine was discontinued, clobetasol proprinate applied and the rash resolved without sequelae in 3 days.