Severe bone marrow aplasia following imatinib mesylate in a patient with chronic myelogenous leukemia.

Imatinib mesylate, a signal transduction inhibitor molecule, has been introduced in the treatment of chronic myelogenous leukemia (CML) since May 2001. By its unique mechanism of action, the drug has revolutionized the management of chronic phase CML. The drug is generally well tolerated. A number of hematological and non-hematological side-effects have been reported. Fatal bone marrow (BM) aplasia has rarely been reported. A 46-year-old women with chronic phase CML was treated with imatinib. Six weeks later she developed severe pancytopenia associated with fever, chest infection and bleeding. A BM biopsy revealed hypoplasia (BM cellularity < 5%). She died of pulmonary mucormycosis. CML patients on imatinib therapy need close monitoring. Those pre-treated with busulfan and interferon-alpha may be at a higher risk of developing BM aplasia.