Abstrait

An Unfortunate Case of Acute Blast Crisis and the Impact of Leukostasis on Morbidity

Maria Carla Canizares-Otero

 Introduction: Blast crisis is an entity seen in both acute and chronic myeloid leukemia. It can be related to the phenomena of hyperleukocytosis and leukostasis, both potentially life-threatening conditions. Hyperleukocytosis is arbitrarily defined as a WBC greater than 100,000/uL; it is widely accepted that the most severe of symptoms occur with WBC at or greater than this value, although severe symptoms can still occur with WBC of only 50,000/uL. An important distinction exists between AML and CLL, as patients with CLL can have WBC elevation greater than 500,000/uL without any appreciable symptoms. This is related directly to the chronic, indolent nature of the disease course in CLL and the lack of acute, cytotoxic cytokine release that is seen in episodes of acute blast crises related to myelocytic or lymphocytic leukemia. The incidence of the phenomenon is not insignificant, with ranges from 5-13% seen in AML and 10-30% in ALL.