Granulomatous bone marrow inflammation during treatment of chronic myeloid leukaemia with interferon alpha-2b

A patient with chronic myeloid leukaemia developed bone marrow granulomas during treatment with interferon alpha-2b. Some granulomas had necrotic centres and giant cells and there was marked eosinophilia surrounding them. The granulomas disappeared when the interferon treatment was discontinued. Mycobacteriosis was ruled out. The most likely explanation for the granuloma formation was drug hypersensitivity.