Secondary hemophagocytic lymphohistiocytosis in zoonoses. A systematic review

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare syndrome that is often fatal despite treatment. It is caused by a dysregulation in natural killer T-cell function, resulting in activation and proliferation of histiocytes with uncontrolled hemophagocytosis and cytokines overproduction. The syndrome is characterized by fever, hepatosplenomegaly, cytopenias, liver dysfunction, and hyperferritinemia. HLH can be either primary, with a genetic aetiology, or secondary, associated with malignancies, autoimmune diseases, or infections. AIM: To focus on secondary HLH complicating zoonotic diseases. MATERIALS AND METHODS: PubMed search of human cases of HLH occurring during zoonotic dise…