Secondary Hemophagocytic Lymphohistiocytosis in Tropical Infections

Abstract Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening, multi-system inflammatory condition that develops because of cytokine overproduction. In both primary and secondary forms, it is often characterized by fever, hepatomegaly, splenomegaly, bi- or trilineage cytopenia, elevated liver enzyme levels, hyperferritinemia, hypertriglyceridemia, and hypofibrinogenemia. It is rare in adults, often unrecognized, and is associated with a high mortality rate. Here we present three cases of tropical infections with accelerated immune response resulting in multisystem inflammation. The first case was due to Scrub Typhus and the second was a result of coinfection of Dengue and Malaria. The third case was due to an opportunistic Histoplasma infection in HIV patient. All the cases satisfied the diagnostic criteria for HLH and showed prompt resolution of symptoms with the treatment of underlying infection.