Acute Monoblastic Leukemia (AML-M5) with Concomitant Hemophagocytic Lymphohistiocytosis: Presenting as Pancytopenia

Hemophagocytic Lymphohistiocytosis (HLH) is an aggressive hyperinflammatory condition characterized by prolonged fever, cytopenias, hepatosplenomegaly and hemophagocytosis with a high rate of mortality. Its diagnosis is a challenge for pathologists as well as clinicians due to variable overlap of symptoms with other severe diseases. AML-associated hemophagocytic lymphohistiocytosis is a rare event, reported only in limited members.

We, hereby report a case of 14 year old male child who came to our hematology department with a history of prolonged fever, pancytopenia and 40 transfusions in last one year. Peripheral blood counts showed 15% blastoid atypical cells. Bone marrow revealed acute leukaemia with evidence of haemophagocytosis. A diagnosis of AML-M5 with HLH was made after flow cytometry and completion of clinico-biochemical criteria for HLH.

Patients with HLH in acute leukaemia may have low blast counts on peripjeral blood leading to much delay in the diagnosis. This case report provides helpful clinical experience related to diagnosis of this rare entity.