Fever, hepatitis and acute interstitial nephritis in a patient with rheumatoid arthritis. Concurrent manifestations of azathioprine hypersensitivity.

We describe a patient with rheumatoid arthritis (RA) who developed hypersensitivity after 3 weeks of therapy with azathioprine with fever, jaundice and renal insufficiency. A percutaneous liver biopsy was compatible with hypersensitivity hepatitis. During azathioprine rechallenge, the symptoms recurred within a few days, consistent with the diagnosis of an acute hypersensitivity reaction. This report is the first to describe the association of an azathioprine induced hypersensitivity simultaneously involving the liver and the kidneys, in the same patient with RA, with resurgence after rechallenge.