Clinical analysis of nervous system complications after hematopoietic stem cell transplantation in children

Objective To explore the incidence, clinical characteristics and prognosis of nervous system(NS) complications after hematopoietic stem cell transplantation (HSCT) in children and further evaluate the occurring risk factors of NS complications and category characteristics. Methods From October 2010 to June 2018, retrospective analysis was performed for 330 HSCT children. Results Twenty-six children developed NS complications after HSCT. Risk factor analysis revealed that the incidence of NS complications were 33.3% in Fanconi anemia, 19.2% in myelodysplastic/myeloproliferative neoplasm (MDS/MPN), 7.3% in acute leukemia, 7.0% in aplastic anemia, 3.1% in genetic immunodeficiency disease, none in other disease (P=0.027). The median age of children with NS complications was 9(4.75-12) versus 6(3-10) (P=0.02) those without NS complications. The incidence of NS complications with and without GVHD>2 degree were 24%(6/25) and 6.6%(20/305)(P=0.002). Different types of NS complications were analyzed, including 53.9% immune-mediated encephalopathy, 26.9% cerebrovascular lesion, one case of transplantation associated thrombotic microangiopathy (TA-TMA), 7.7% drug therapy-related toxic encephacopathy, 3.8% metabolic encephalopathy and 7.7% peripheral neuropathy. The mortality of NS complications was 34.6% and those with immune-mediated encephalopathy had the highest mortality (13/19, 68.4%). However, those with drug therapy-related toxic encephacopathy, metabolic encephalopathy and peripheral neuropathy all survived after HSCT. The overall survival rate was higher in children without NS complications than those with NS complications. Conclusions The incidence of NS complications after HSCT is correlated with primary diseases, age and GVHD >2 degree. Children with drug therapy-related toxic encephacopathy, metabolic encephalopathy and peripheral neuropathy have better prognosis than those with immune-mediated encephalopathy and TA-TMA. Reducing NS complications may improve long-term survival of children after HSCT. Key words: Children; Hematopoietic stem cell transplantation; Nervous system complications; Risk factors; Long term survival