Transient thrombocytosis with megathrombocytes in a case of acute myeloblastic leukemia.

Thrombocytosis is commonly seen in reactive conditions and certain neoplastic states, such as chronic myeloproliferative disorders. It is rarely seen in acute leukemia. A 12-year-old girl with acute myeloblastic leukemia (FAB M2) in remission presented with pyoderma. Her hemogram revealed anemia (Hb-6.4g/dl), leucopenia (TLC - 1.2 x 109/L) and thrombocytosis (platelet count- 580 x 109/L). A peripheral blood film showed numerous abnormally large platelets with few atypical cells. The thrombocytosis subsided with the clearance of infection but atypical cells persisted. One month later, she relapsed. Cytogenetic analysis revealed variable results (trisomy 9 and deletion 3). This case has been presented because thrombocytosis is rare in AML and its appearance calls for a close follow-up.