A Single-center Retrospective Report Therapies and Treatment Responses for Hemophagocytic Lymphohistiocytosis in Children: Is Blood Purification Beneficial?

Abstract

Abstract Background Hemophagocytic lymphohistiocytosis (HLH) is a severe and life-threatening systemic inflammatory disorder. This study aims to evaluate the effectiveness of different therapies and identify early treatment responses as potential indicators to adjust subsequent treatments. Methods A retrospective review of HLH patients was conducted at Zhujiang Hospital, Southern Medical University (Guangzhou, China) from January 1, 2012 to December 31, 2022. The study used Cox regression to identify prognostic risk factors. Causal mediation analysis assessed the impact of various treatments on overall survival, specifically through the mediator of complete remission at 4 or 8 weeks. Results The study involved 102 patients, with 31 receiving HLH-94 protocol treatment and 22 receiving HLH-04. Among 78 pediatric intensive care unit patients, 13 underwent blood purification alone, while 22 underwent blood purification with HLH-94/04 protocol treatment. Central nervous system involvement, elevated lactate dehydrogenase levels, and blood purification alone were associated with poor prognoses (P < 0.05). Achieving complete remission at 4 or 8 weeks is a positive prognostic indicator(P < 0.05). HLH-94/04 protocol treatments had higher survival rates (81.3% and 76.6%) than blood purification alone or combined with HLH-94/04 protocol treatments, which had significantly lower survival rates (23.4% and 15.4%). Patients who achieved complete remission at 4 or 8 weeks had a higher survival rate of 90.7% and 92.3%, respectively. Conversely, Partial or no response at 4 or 8 weeks had a significantly lower survival rate of 2.9% and 3.4%, respectively. Compared to HLH-94 protocol treatment, blood purification alone has a 33.28% effect mediated by inducing complete remission at 4 weeks, which decreases to 26.56% at 8 weeks. Blood purification combined with HLH-94/04 protocol treatment with higher mediation effect was 79.88% at 4 weeks compared to 51.95% at 8 weeks. Conclusion HLH-94/04 protocol treatments resulted in complete remission and improved survival rates compared to blood purification alone in pediatric HLH patients. Further investigation is necessary to determine the efficacy of blood purification in combination with these treatments. Comparing complete remission at 4 weeks to that at 8 weeks may be a better mediator on overall survival.