The aim of study was to establish an accurate and stable technique for the detection of NK cell activity in the diagnosis of hemophagocytic lymphohistiocytosis(HLH).

Objective to study the characteristics of pathogen, clinical and laboratory features, treatment and prognosis of EBV-associated Hemophagocytic lymphohistiocytosis (EBV-HLH).

Objective To study the clinical features, risk factors and rational treatment of hemophagocytic lymphohistiocytosis (HLH) in children.