Case report: patient with unexplained high fever and pancytopenia.

OBJECTIVE AND IMPORTANCE: We present a case of hemophagocytic lymphohistiocytosis (HLH), giving insight in how to establish diagnosis and start appropiate treatment.

CLINICAL PRESENTATION: A 45-year-old male presented at the emergency ward with high fever and pancytopenia. Repeat bone marrow aspirates showed hemophagocytosis. Extensive work-up with exclusion of other infectious and malignant diseases, eventually lead us to the diagnosis of hemophagocytic lymphohistiocytosis.

INTERVENTION: The patient was treated with Etoposide, Cyclosporine A, and systemic steroids based on the HLH-2004 protocol. Unfortunately the patient responded very poorly to the treatment with prolonged pancytopenia, leading to central hemorrhage and eventually death.

CONCLUSION: Diagnosis of hemopagocytic lymphohistiocytosis is difficult and late because of aspecific signs and low incidence. The HLH-criteria can be of use to exclude or confirm diagnosis in unclear cases. Early diagnosis and treatment is crucial given high morbidity and mortality. Therapy depends on type and etiology of the HLH-syndrome. Besides treating the possible triggering factor, Etoposide, steroids, and Cyclosporine A are the mainstays of treatment, sometimes followed by allogenic hematopoietic stem cell transplantation. More research in adults is needed.