Experience with Hemophagocytic Lymphohistiocytosis in Adults: A Retrospective Study of 56 Patients in a Single Institute of China

The median age at diagnosis was 34 (range, 14–83 years). The male to female ratio was 1.95:1. Regarding etiologies, 43 patients (76.8%) were MHLH, 4 patients (7.1%) were IHLH, 1 patient (1.8%) had CTD, and for the remaining 8 patients (14.3%) the underlying cause could not be determined. Of the 43 cases of MHLH, 23 patients (53.5%) had Mature T- and NK-cell neoplasms; 10 patients (23.2%) had mature B-cell neoplasms; 1 patients (2.3%) had B lymphoblastic leukaemia; 2 patients (4.7%) had Hodgkin lymphomas, and the remaining 7 patients (16.3%) had unclassified hematological malignancies. The clinical characteristics and laboratory findings were summarized in Table. 1, and compared with literature (GE Janka, 2007) our patients had lower triglycerides and higher ferritin levels. The median time from symptoms to diagnosis was 1.4 months (range, 0.1–24.0 months), the median time from admission to diagnosis was 2 days (range, 0–30 days). Interestingly, patients admitted to departments other than the hematology department had significantly longer time for diagnosis (16 versus 2 days, P<0.001). Most patients were treated with HLH-04 based therapy, including steroid (54/56, 96.4%), cyclosporine (36/56, 64.3%), and etoposide (29/56, 51.8%). In MHLH patients, 19/43 patients (44.2%) received chemotherapy. Infection complicated the course in 45/56 (80.4%) patients. The median follow-up time of the survived patients was 300 days (range, 63–825 days). Seven patients lost follow-up, 38 patients died, 11 patients survived. The median survival time was 28 days (range, 0–825 days). The modality rate was 67.9%, and the major cause of death was multiple organs failure. MHLH had significantly shorter survival time than non-malignancy HLH (P=0.05, Figure 1). Cox proportional hazard model indicated that age, hypoalbuminemia and hypofibrinogenemia were the risk factors of poor prognosis.