Certified Pediatric Hematology Oncology Nurse (CPHON) Practice Exam

The most common metabolic disorder of red blood cells worldwide is glucose-6-phosphate dehydrogenase deficiency (G6PDD). This enzymatic deficiency is linked to the inability of red blood cells to properly handle oxidative stress, which leads to hemolytic anemia. G6PD is an essential enzyme in the pentose phosphate pathway, and its absence makes red blood cells more vulnerable to various oxidative agents, including certain medications, infections, and foods such as fava beans.

G6PDD is particularly prevalent in regions of the world where malaria is endemic, as the disorder provides a protective advantage against malaria due to the reduced lifespan of affected red blood cells which makes it harder for the malaria parasites to survive. This evolutionary aspect contributes to its widespread occurrence, especially in Southeast Asia, Africa, and parts of the Mediterranean.

While other conditions such as iron deficiency anemia, sickle cell disease, and aplastic anemia are also significant health concerns, they do not have the same global prevalence specifically in terms of enzymatic deficiency. Iron deficiency anemia, for instance, is a nutritional deficiency but not a metabolic disorder of red blood cells in the same way as G6PD deficiency. Sickle cell disease is a genetic disorder that affects hemoglobin structure rather than