A novel mutation in Wiskott-Aldrich syndrome and successfully treated with umbilical cord blood transplantation.

We report a novel mutation in a boy with Wiskott-Aldrich syndrome (WAS) who was 4 years and 10 months of age and underwent successful umbilical cord blood transplantation (UCBT). The child presented at 3 months of age with symptomatic thrombocytopenia and eczema. Despite a large dose of intravenous immunoglobulin treatment, no increase in the platelet count was observed. A genetic analysis revealed a deletion mutation at c.410_419del10 in exon 4, which resulted in the replacement of encoded phenylalanine with serine at amino acid 137 and caused an early stop codon at downstream amino acid 121 (p.F137SfsX121), and confirmed a diagnosis of WAS. The only curative treatment for WAS is hematopoietic stem cell transplantation. Because no matched sibling donor was available, he underwent unrelated UCBT. He is currently alive and doing well at fourteen months post-transplant, and he is free of any bleeding episodes. The eczema that was all over his body had disappeared. This case suggests that unrelated UCBT may be safe and technically feasible for the treatment of WAS when an appropriately matched related or unrelated donor is unavailable.