Systemic Hypersensitivity to Allopurinol with Acute Interstitial Nephritis

A patient with a history of iridocyclitis and discrete IgA glomerulonephritis had two severe systemic reactions to allopurinol with fever, macular rash, and prolonged renal insufficiency without hypertension, edema or a nephritic sediment. Upon controlled re-exposure, cutaneous vasculitis and acute interstitial nephritis were observed. Immunohistology only showed granular C3 deposits to the tubular basement membrane. Circulating antibodies to tubular basement membranes were positive. After several months, serum creatinine had almost returned to initial levels.