Glucose-6-Phosphate Dehydrogenase (G6PD), erythrocytes

Glucose-6-phosphate dehydrogenase catalyzes the first step in the pentose phosphate shunt, oxidizing glucose-6-phosphate (G-6-P) to 6-phosphogluconate (6-PG) and reducing NADP to NADPH.

G-6-P + NADP _(G-6-PDH)_> 6-PG + NADPH

The rate of production of NADPH is proportional to G6PD activity. G-6-PDH deficiency is the most common enzymatic deficiency of the red cell. G6PD assay is indicated in the following conditions: drug-induced hemolytic anemia, favism, neonatal icteric and nonspherocytic congenital hemolytic anemia.