Interferon alpha (IFN) is the drug of choice for the treatment of chronic viral hepatitis. Its administration is associated with the risk of development of some undesirable effects. One of the possible rare complications of treatment is sarcoidosis. A 64-year-old man with chronic hepatitis B (HBsAg, HBeAg, HBV DNA positive) was treated for 28 weeks with recombinant IFN. In the course of treatment HBV DNA disappeared from serum, seroconversions of HBeAg/anti-HBe and HBsAg/anti-HBs occurred as well as normalization of ALT. The tolerance of treatment was very good. Twelve months after treatment the patient had an X-ray examination of the lungs (preventively before an ophthalmological operation) and enlarged nodes in the pulmonary hili were found (before treatment with IFN the X-ray finding was normal). Therefore CT examination of the chest was made and lymphadenopathy of the anterior and middle mediastinum was revealed. Endoscopic sonography confirmed enlargement of numerous paraoesophageal and tracheobronchial lymph nodes, fusing partly into packets. During subsequent dextrolateral thoracoscopy a lymph node with a diameter of 27 mm was excised. Histological examination of the node revealed granulomatous lymphadenitis corresponding to sarcoidosis. The patient was followed up at the outatient department, medicamentous treatment of sarcoidosis was not indicated. Within one year after thoracoscopy complete normalization of the lymph nodes occurred (X-ray and CT of the lungs). According to the authors this is the first published case of sarcoidosis which developed in conjunction with treatment of chronic hepatitis B with alpha interferon.

        Key words: chronic hepatitis B – alpha interferon – sarcoidosis