Epidemiological Investigation of Hemophagocytic Lymphohistiocytosis in China
Abstract Background. At present, most research on HLH focus on etiology and therapy, leaving few epidemiological reports. The published studies of China are mainly regional investigations. We aim to present the overall epidemiological status of HLH in China, and provide Chinese data for the international HLH epidemiological investigation. Methods. The data of HLH cases in China in 2019 was collected and statistically analyzed. Findings. Among 1445 cases in 31 areas, EBV accounting for 44.01% is the most common cause. Lymphoma-associated HLH patients are mostly males (P<0.05) while rheumatic and immune-associated HLH mostly females (P<0.001). Children have mainly primary HLH and EBV-associated HLH (P<0.001) while adults mostly tumor-associated HLH. Lymphoma-associated HLH is positively correlated with the age of onset (P<0.01). The diagnosis rate of 29 areas has a significant correlation with per capita Gross domestic product (P<0.05). Conclusion. The etiology distribution of HLH in different age and sex is different, assisting clinicians with the diagnosis of HLH; The diagnosis rate of regions with a high incidence of HLH in China is not ideal as the result of the effect of the local economic level indicating the importance of improving the regional medical level.