Investigation of hemophagocytic lymphohistiocytosis in severe sepsis patients

Abstract Purpose Hemophagocytic lymphohistiocytosis(HLH) is a life-threatening condition characterized by uncontrolled inflammation and has common clinical and laboratory features with sepsis. The aim of this study was to investigate patients treated with severe sepsiswho had bicytopenia for the presence of HLH. Materials and methods Patients with severe sepsiswho were non-responsive to treatment and developed at least bicytopenia were included. Peripheral blood samples were collected and stored for later evaluation for natural killer (NK) activity and soluble interleukin-2 receptor levels. Diagnostic criteria of HLH were retrospectively analyzed. Results Seventy-five of 382 patients (20%) were followed as severe sepsisand septic shock. Among them, 40 patients had bicytopenia. Twenty-six of 40 patients were excluded due to the presence of active solid or hematological malignancies. Three patients died before fulfillment of HLH criteria and one patient denied to give consent. All of the remaining 10 patients had at least five of the eight criteria according to criteria of the HistiocyteSociety. Only one of 10 patients was diagnosed as HLH and received treatment during intensive care unit stay. None of the 10 patients survived. Conclusions This study emphasizes to consider the possibility of HLH and the need of rapid assessment of patients with severe sepsiswho had bicytopenia and were resistant to treatment in intensive care.