Unrelated Umbilical Cord Blood Transplantation For Children With Hereditary Leukodystrophy: Single Center Experience

Background Hereditary leukodystrophies are diverse metabolic diseases caused by gene mutations that result in the abnormal development or degeneration of myelin. Transplantation of matched sibling donor umbilical cord blood (UCB) can slow progression and prolong survival in some cases. For patients without siblings, however, UCB transplantation from unrelated donors may be the only option. Methods This retrospective study assessed unrelated UCB transplantation (UCBT) efficacy following busulfan- and cyclophosphamide-based myeloablative chemotherapy. Results The study cohort included 12 pediatric patients (ten males), nine with adrenoleukodystrophy (ALD) and three with globoid cell leukodystrophy (GLD), treated between April 2015 and March 2020. All received HLA-matched or partially mismatched UCBT. Median age at UCBT was 7.2 years (range, [0.8–12.9 years]). There were no cases of graft rejection. Median neutrophil engraftment time was 20 days [12–33 days] and median platelet engraftment time was 29 days [14–65 days]. Median follow-up was 28 months [1–73 months], and overall survival rate was 83.3% (10/12). Seven patients had higher Loes scores post-transplantation, and two patients died of infection. Four patients with rapid neurological deterioration pre-UCBT exhibited worse neurological symptoms post-UCBT. In contrast, four patients with stable neurological symptoms pre-UCBT demonstrated symptom stability post-UCBT, and two with no neurological symptoms pre-UCBT were also symptom-free post-UCBT. Further, lipid profiles of surviving ALD patients were improved post-treatment. Conclusions Hereditary leukodystrophy patients with mild neurological symptoms can benefit from UCBT, while UCBT cannot reverse advanced disease.