Child with Wiskott–Aldrich syndrome underwent atypical immune reconstruction after umbilical cord blood transplantation: A case report

BACKGROUND: Timely reconstitution of a donor-derived immune system is important for recovery and long-term survival of patients after allogeneic hematopoietic stem cell transplantation (HSCT). We describe a case of Wiskott–Aldrich syndrome (WAS) treated by umbilical cord blood transplantation (UCBT) with atypical immune reconstruction. CASE SUMMARY: A 1-year-old Chinese male infant was diagnosed with WAS. WAS gene sequencing identified the mutation c.777 + 1G>A (IVS8). On August 8, 2017, he was admitted to our hospital for HSCT. We selected an unrelated Human leukocyte antigen 6/10-matched donor for UCBT. After HSCT, the immune reconstitution process was atypical, the lymphocytes reached 0.5 × 10(9)/L on day 23, and the neutrophils reached 0.5 × 10(9)/L on day 34. The patient’s recovery throughout the year was good. CONCLUSION: An increase in lymphocytes (especially T cells) earlier than granulocytes may be a marker of a good prognosis in UCBT.