[Infantile visceral leishmaniasis, an etiology of easily curable hemophagocytic lymphohistiocytosis syndrome].

Infantile visceral leishmaniasis associated hemophagocytic lymphohistiocytosis (HLH) is a rare clinicopathological entity, difficult to diagnose and fatal if untreated. The diagnosis should be considered in young infants with fever and splenomegaly. We report two cases of HLH caused by visceral leishmaniasis. In the first case, a 3-month-old boy was admitted with fever and pancytopenia, leading to the diagnosis of HLH based on complete clinical and biological features including hemophagocytosis on bone marrow smears. Investigations for an underlying genetic, metabolic disease and an infectious trigger were negative. Primary or genetic hemophagocytic syndrome was suspected and immunosuppressive treatment (steroids and cyclosporin) was instituted. A second bone marrow examination performed 1 month later revealed leishmania. The boy was treated with liposomal amphotericin and recovered rapidly. In the second case, a 10-year-old child was hospitalized with fever, pancytopenia, and a tumoral syndrome. He had a history of recurrent infections. The bone marrow biopsy showed leishmania and treatment with liposomal amphotericin was delivered. After 3 days of treatment, the improvement was judged inadequate and the boy presented biological signs of HLH. He was treated with steroids. An underlying primary immunodeficiency (interleukin-12/interferon-γ axis disorder) was secondarily diagnosed.