Hematopoietic stem cell transplantation for purine nucleoside phosphorylase deficiency with two novel mutations: a case report and review of literature.

Purpose: We report the case of a 6-year-old boy who presented with muscular hypertonia, impaired growth, and recurrent infections, who was diagnosed with purine nucleoside phosphorylase (PNP) deficiency with two novel mutations in the PNP gene. He underwent a hematopoietic stem cell transplantation (HSCT) from an unrelated donor, and we observed the clinical outcome.

Methods: We retrospectively analyzed the clinical manifestations and outcomes of this patient who underwent HSCT. We analyzed the results of whole exome sequencing (WES) on the patient.

Results: The patient experienced repeated serious respiratory and gastrointestinal infections since birth and presented with neurological symptoms. He was found to have two novel pathogenic mutations in the PNP gene through WES. One hemizygous variant was c.385dup (p.Ile129Asnfs*6) in exon 4. The other was a heterozygous deletion in exon 2-6. He underwent HSCT with clinical improvement.

Conclusions: We presented a patient with two novel mutations in the PNP gene and clinical improvement following an allo-HSCT.