The Use of Bone Marrow Transplantation (BMT) or Hematopoietic Stem Cell Transplantation (HSCT) in Pediatric Patients Diagnosed With Ataxia-Telangiectasia: A Systematic Review.

Ataxia-telangiectasia (A-T) is a rare neurological disorder that leads to early death due to immunodeficiency, leukemia, and lymphoma. Given the underlying immune dysfunction and predisposition to hematologic cancers, bone marrow transplantation (BMT) or hematopoietic stem cell transplantation (HSCT) has emerged as a potential therapeutic strategy in pediatric patients with A-T. Therefore, longer follow-ups are needed to assess associated risks, side effects, procedures, and eligibility criteria. This systematic review aims to fill this gap by consolidating evidence from different parts of the world on the use of HSCT in pediatric patients diagnosed with A-T. The study used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to search five databases (PubMed, Web of Science, ScienceDirect, Google Scholar, and MEDLINE) for relevant published papers. The review covered studies on both classical and variant forms of A-T. The studies included are those with primary outcomes related to engraftment success, immunological reconstitution, survival rates, transplant-associated toxicity, infection prevalence, cancer management, and neurological progression. Only papers published in English between 2010 and 2024 were eligible for inclusion. Two experienced researchers independently assessed the retrieved papers for inclusion. A structured data collection sheet was used to retrieve relevant information from the selected articles. The risk of bias of the items included prospective and retrospective, cross-sectional, and cohort studies was assessed using the Newcastle Ottawa Quality Assessment Scale. Eight studies were included, comprising various designs including prospective, retrospective, and population-based cohorts. Among these, three studies reported actual use of HSCT or BMT in pediatric patients with A-T, showing immune reconstitution and reduced infections, but limited impact on neurological decline. Reduced-intensity conditioning (RIC) was associated with better survival and fewer complications compared to myeloablative regimens. The remaining studies discussed HSCT theoretically or focused on supportive care, immunological profiles, cancer risk, or nutritional challenges. Overall, outcomes varied, with limited evidence supporting routine use of HSCT in A-T due to associated risks and uncertain long-term benefits. In conclusion, HSCT shows potential in improving immune function and reducing infections in A-T patients. However, it has minimal effect on halting neurological progression. Given the risks and limited long-term data, HSCT is not currently recommended as a standard treatment for A-T.