Azathioprine-associated interstitial pneumonitis

Background: An early hypersensitivity reaction and late bone marrow depression are well known side-effects of azathioprine; interstitial pneumonia is a rare complication. Case report: A 40-year-old male patient was treated with azathioprine due to extensive ulcerative colitis for 10 years. He complained of 7 days of fever, cough and catarrhal signs, without symptoms of active colitis. Opportunistic infections were ruled out. The chest X-ray, CT and lung biopsy demonstrated the presence of interstitial inflammation. The azathioprine therapy was discontinued as the potential source of the pulmonary infiltrate. As…