To evaluate the efficiency of HLH-04 protocol on children with EBV-hemophagocytic lymphohistiocytosis (EBV-HLH).

The clinical features, rates of therapeutic response and prognosis of 12 children with EBV-HLH which were diagnosed and treated in the department of Pediatrics, Second Affiliated Hospital, Sun Yat-Sen University during April 2005 to April 2008, were retrospectively analyzed. All patients fulfilled the diagnostic criteria for EBV-HLH according to the HLH-04 protocol, namely, positivity for the EBV genome and positive anti-viral antibody in the blood. The therapeutic protocol was based on the HLH-04 protocol with some changes if the effect was poor or the side effects of drugs were serious, such as teniposide instead of etoposide, cellcept instead of cyclosporine A, or cellcept + cyclosporine A instead of etoposide.

①Clinical features: All the 12 EBV-HLH patients had persistent hyperpyrexia, splenomegaly and hematocytopenia. 1 had convulsion. Serum ferritin in 8 cases was over 500 mg/L, triacylglycerol in 6 cases was over 3.0 mmol/L, fibrinogen in 5 cases was less than 1.5 g/L, the amount of the natural killer cell in 8 cases was decreased, and the hemophagocytosis was found in 12 cases of bone marrow biopsy examination. ②Treatment response: 1 patient quit the treatment after final diagnosis, and the median follow-up time of the other 11 patients were 17 months (10~36 months). During the early stage of treatment, the median time for complete remission (CR) was 21 days. 10 achieved complete remission at the 14th~42th day, 1 could not achieve remission (NR) after 112 days, but teniposide and cellcept was given and the patient achieved complete remission at day 118 and kept continue complete remission (CCR) finally. During the maintenance stage, 9 patients achieved continue complete remission and their continue complete remission time was 9~32 months. And 8 cases withdrew drus, the time of drug withdrawal were 1~19 months, 1 patient lost follow-up after 11 months of treatment because of relapse. 1 patient relapsed 10 months later after drug withdrawal, who was receiving drug treatment subsequently.

Most of EBV-HLH children can be effectively controlled by immunochemical therapy based on the HLH-04 protocol. Etoposide can be replaced with teniposide if its effect is bad; and cellcept is another feasible choice for those who are not tolerant CsA or cannot achieve good effect.