Diagnostics and treatment of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a hyperferritinemic hyperinflammatory syndrome. A primary hereditary form can be distinguished from a secondary acquired form. In adults the secondary form accounts for the vast majority of cases. Infections, malignancies and autoimmune disorders are common triggering factors of secondary HLH. Persistent fever, bicytopenia or pancytopenia and splenomegaly represent major symptoms in HLH and occur in virtually all patients. The diagnosis of HLH is made on the basis of the HLH-2004 criteria. The probability of the presence of HLH can be estimated using the HScore. Patients with HLH require immunosuppressive treatment. Hence, high doses of corticosteroids represent the cornerstone of treatment. Furthermore, immunoglobulins, anakinra, ruxolitinib or etoposide are given depending on the triggering factor. The course and prognosis of HLH are dependent on the early initiation of treatment, the triggering factor and the response to treatment.