A Case of Inflammatory Bowel Disease and a Rare Lymphoma on Azathioprine Therapy

Abstract

A 23 year old man with a history of ulcerative colitis (UC) and overlap primary sclerosing cholangitis (PSC)/autoimmune hepatitis (AIH) with frequent biliary stenting and progression to cirrhosis presented with fever of unknown origin (104 degrees F). Both UC and PSC were diagnosed as an infant, and his immunotherapy consisted of mesalamine, azathioprine, or prednisone. At the time of presentation, he was completely naive to anti-TNF therapy and no longer on steroids. His complaints were mainly fatigue and inability to focus. Physical exam was unremarkable except for right upper quadrant tenderness. He had been previously doing well on his immunosuppressive regimen, with no medication changes or recent flares. Laboratory studies were remarkable for elevated transaminases, cholestasis, and significant pancytopenia [WBC 2900/uL, Hgb 10.3 g/dL, Plt 76,000/uL]. Computed tomography (CT) of the abdomen revealed a massively enlarged spleen. Throughout his admission, he became increasingly pancytopenic and ultimately neutropenic despite broad spectrum antibiotic therapy [WBC 1100/uL, ANC 600/uL, Hgb 8.5 g/dL, Plt 37,000/uL]. Extensive viral serologies were all negative except for a positive EBV PCR. On hospital day 3, he underwent an ERCP to evaluate for possible cholangitis. Several nonbleeding localized erosions were found in the gastric fundus and body as well as diffuse erythematous gastropathy. Stomach biopsies revealed a high grade plasmablastic lymphoma (PBL). His prior endoscopies were all normal. Given the high risk for extra-gastric involvement in the setting of an aggressive lymphoma, he was started on a regimen of dose adjusted EPOCH chemotherapy and radiotherapy. He did well after chemotherapy and is currently in remission. PBL is a relatively new clinical entity described as a distinct subtype of diffuse large B-cell lymphoma, characterized by its aggressive nature and plasmacytic differentiation. The exact incidence of PBL is not known, but nearly all reported cases are associated with HIV infection or in patients on immunosuppression. It has been noted in some instances to be present in association with other entities, such as IBD. Despite a handful of case reports available to date, there are no reports documenting the diagnosis of PBL in patients with IBD in the absence of anti-TNF or in patients on thiopurines. Having reviewed the available literature, this would be the first case of PBL in a patient with UC on azathioprine therapy.Figure 1Figure 2