Giant cell tubulitis with immune complex deposits in a patient with lupus nephritis.

We report a case of acute tubulointerstitial nephritis with giant cell tubulitis and tubular basement membrane immune complex deposits in a patient with membranous lupus nephritis. The patient, who had no prior evidence of lupus nephritis, developed acute kidney failure and mild proteinuria after cardiac valve replacement surgery. Giant cell tubulitis with tubular basement membrane immune complex deposits has been described in 4 patients after cardiac surgery, 3 of whom received cefuroxime, suggesting the possibility of a drug hypersensitivity reaction. The present case suggests there may also be a pathogenetic role for autoimmunity in this condition.