Hemophagocytic syndrome in children with acute monoblastic leukemia-another cause of fever of unknown origin.

PURPOSE

Intensification of antileukemic treatment and progress in supportive management have improved the survival rates of children with acute myeloid leukemia (AML). However, morbidity and early mortality in these patients are still very high, especially in children with acute monoblastic leukemia (AML FAB M5). Inflammatory syndromes complicating the management of these children after application of cytosine arabinoside and due to hyperleukocytosis at initial presentation have been reported. Hemophagocytic lymphohistiocytosis (HLH) has been described as a serious and life-threatening acute complication during treatment of different oncologic entities; however, data on HLH in children with AML FAB M5 are extremely rare.

METHODS

A retrospective study of all children with AML FAB M5 treated at our institution between 1993 and 2013 was performed to describe the clinical characteristics of patients who developed an inflammatory syndrome with HLH during oncologic treatment.

RESULTS

Three of 10 children developed an inflammatory syndrome with fever, elevation of C-reactive protein, hyperferritinemia, elevation of soluble interleukin-2, and hemophagocytosis during prolonged aplasia following the first cycle of chemotherapy not responding to broad-spectrum antibiotics. No infectious agents could be identified; the initial symptoms occurred 17, 18, and 28 days after diagnosis of AML, respectively. The children immediately responded to dexamethasone; however, the same syndrome was observed again after the second cycle of chemotherapy and, in one patient, also after the third cycle.

CONCLUSIONS

Treating physicians should be aware of an inflammatory syndrome resembling HLH in children with monoblastic leukemia since this problem might extremely complicate management and supportive care of these children. The co-incidence of monoblastic leukemia with HLH might be explained by cytokines released from the monoblastic leukemic cells themselves.