Eosinophilic enteritis observed during alpha-interferon therapy for chronic hepatitis C

We report a patient with chronic hepatitis C who developed eosinophilic ent eritis while being treated with recombinant interferon alpha-2b. He had no history of either allergic disorders or recurring episodes of abdominal cra mps, nausea, or diarrhea. He also had had a normal eosinophil count prior t o the interferon treatment. After a 12-week course of interferon alpha-2b, he began to complain of severe abdominal pain, diarrhea, and abdominal full ness. His peripheral eosinophil count increased to 45% (absolute count, of 7610/mu l). Abdominal ultrasonography and computed tomography revealed diff use thickness of the intestinal wall with gross ascites that contained nume rous eosinophils. An upper gastrointestinal barium study with small bowel f ollow-through showed an edematous mucosal layer of the jejunum and ileum. T here was a spectacular relief of the patient's subjective symptoms after th e administration of prednisolone. Follow-up studies revealed resolution of the ascites and the mucosal layer edema and normalization of the peripheral eosinophil count. Prednisolone was tapered off, but the eosinophilic enter itis did not recur. As there had been no evident exposure to common causati ve factors for eosinophilic enteritis, we suggest that interferon alpha-2b could thus have played a role in the triggering of the eosinophilic enterit is.