Fatal thrombocytopenia temporally related to the administration of alemtuzumab (MabCampath) for refractory CLL despite early discontinuation of therapy

Abstract

Alemtuzumab (Campath 1H -MabCampath), initially used for prophylaxis of graft versus host disease in allogenic transplantaion, is now increasingly used for refractory chronic lymphatic leukaemia (CLL). Its efficacy has been well documented in this - the commonest form of leukaemia. Alemtuzumab is associated with severe immunosuppression, allergic reactions and thrombocytopenia. Data sheet and information supplied by the manufacturer confirm the rare occurrence of serious immune thrombocytopenia, recommending discontinuation of therapy when platelet counts fall below 50 × 10 9/l. We report a patient with refractory CLL in which relentless progressive cytopenia occurred despite the discontinuation of alemtuzumab therapy while the platelet count was over 97 × 10 9/l. Marrow biopsy showed increased megakaryocytes, the patient bleed uncontrollably and died of cerebral haemorrhage with a platelet count < 10 × 10 9/l. Data on the predictive factors underlying this complication are few and deserve further study as this drug is increasingly used the treatment of CLL. © 2004 Taylor & Francis Ltd.