First Reported Case of Glucose-6-Phosphate Isomerase Deficiency in a Saudi Child With Hemolytic Anemia.

Glucose-6-Phosphate Isomerase (GPI) deficiency constitutes a rare autosomal recessive enzymopathy that causes hereditary nonspherocytic hemolytic anemia (HNSHA). The condition is linked to homozygous or compound heterozygous mutations in the GPI gene located on chromosome 19q13. This enzyme deficiency disrupts glycolysis, leading to hemolysis of red blood cells. This report documents the first Saudi patient officially diagnosed with GPI deficiency. The diagnosis was conclusively established using whole-exome sequencing (WES), which identified a homozygous pathogenic variant in the GPI gene.