Outcome of Non-hematological Autoimmunity After Hematopoietic Cell Transplantation in Children with Primary Immunodeficiency

Purpose Knowledge of post-hematopoietic cell transplantation (HCT) non-hematological autoimmune disease (AD) is far from satisfactory. Method This multicenter retrospective study focuses on incidence, risk factors, and outcomes of post-HCT AD in 596 children with primary immunodeficiency (PID) who were transplanted from 2009 to 2018. Results The indications of HCT were severe combined immunodeficiency (SCID, n = 158, 27%) and non-SCID PID ( n = 438, 73%). The median age at HCT was 2.3 years (range, 0.04 to 18.3 years). The 5-year overall survival for the entire cohort was 79% (95% cumulative incidence (CIN), 74–83%). The median follow-up of surviving patients was 4.3 years (0.08 to 14.7 years). The CIN of post-HCT AD was 3% (2–5%) at 1 year post-HCT, 7% (5–11%) at 5 years post-HCT, and 11% (7–17%) at 8 years post-HCT. The median onset of post-HCT AD was 2.2 years (0.12 to 9.6 years). Autoimmune thyroid disorder ( n = 19, 62%) was the most common post-HCT AD, followed by neuromuscular disorders ( n = 7, 22%) and rheumatological manifestations ( n = 5, 16%). All patients but one required treatment for post-HCT AD. After multivariate analysis, age at transplant ( p = 0.01) and T cell–depleted graft ( p