A pyruvate kinase deficiency child with novel PK-LR gene mutations was successfully cured by matched unrelated donor peripheral blood stem cell transplantation.

Background: Pyruvate kinase deficiency (PKD) is an autosomal recessive disorder caused by a PK-LR gene mutation. Allogeneic hematopoietic cell transplantation (HCT) is an effective cure for PKD. However, the experience of applying HCT in PKD is limited.

Methods: We present a child with novel PK-LR gene mutations who was successfully cured by matched unrelated donor peripheral blood stem cell transplantation (MUD-PBSCT).

Results: A 4-year-old, male patient suffered severe hemolytic anemia and jaundice 5 h after birth. Gene sequencing showed that the pyruvate kinase-liver and RBC (PK-LR) gene had a nonsense mutation in exon 5: c.602G>A (p.W201X), and large deletions in exons 3-9. Both of them were novel pathogenic mutations of the PK-LR gene. After transplantation, the hemoglobin level became normal and the nonsense mutation was undetectable. Grade Ⅳ acute graft-versus-host disease (aGVHD) and extensive chronic graft-versus-host disease (cGVHD) occurred in the patient. However, the GVHD was controlled effectively. The patient is alive and has good quality of life 22 months post-transplant, but has mild oral lichen planus-like lesion.

Conclusion: Gene sequencing contributes to the diagnosis of PKD. HCT is an effective method for curing PKD, but we should explore how to reduce severe GVHD.