Glucose-6-Phosphate Dehydrogenase Deficiency in Newborns

Glucose-6-phosphate dehydrogenase Deficiency Prevalence by Geographic Area

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common enzyme disorder diagnoses, affecting more than 400 million people worldwide.

Glucose-6-phosphate dehydrogenase deficiency is most common in Africa, the entire Mediterranean basin, the Middle East, and Southeast Asia. This geographic distribution is close to that of malaria, suggesting a relationship between the two diseases.

Clinic

G6PD catalyzes the first shunt step of monophosphate hexoses, oxidizing glucose-6-phosphate in 6-phosphogluconolactone and reducing NADP to NADPH. This metabolic pathway is the only erythrocyte source of NADPH, an important cofactor in glutathione metabolism and whose primary function is to protect red blood cells from oxidative damage caused by binding between hemoglobin and oxygen. In individuals with a glucose-6-phosphate dehydrogenase deficiency diagnosis, G6PD will therefore lead to a decrease in the concentration of antioxidant agents (NADPH and glutathione) within red blood cells. This leads to excessive oxidation of hemoglobin and other proteins, leading to loss of function and cell lysis.

The clinical spectrum of glucose-6-phosphate dehydrogenase deficiency is broad. The severity of the disease and the probability of developing neonatal jaundice or chronic hemolysis, as well as the extent of hemolysis when hemolytic episodes occur, depend on the degree of enzyme deficiency, which is itself determined by the genotype. Patients are most often asymptomatic, but many individuals may experience episodes of episodic anemia. A few have chronic hemolytic anemia.

In addition, acute hemolytic attacks may be triggered when oxidative stress occurs, such as when certain drugs (and chemicals) are taken, or when certain foods such as beans (favism) or quinine-based beverages are consumed, or when acute infections occur.

Glucose-6-Phosphate Dehydrogenase Deficiency Treatment

The management of G6PD deficiency is essentially preventive and is based on measures limiting any oxidative stress towards red blood cells. Implementation is usually easy once the diagnosis is known. However, some acute hemolytic attacks can occur after taking an oxidizing drug or after an uncontrolled infection. In these contexts, management depends on the severity of hemolysis and anemia.

Heredity

The transmission of glucose-6-phosphate dehydrogenase deficiency is linked to the X chromosome. The disease is therefore mainly expressed in male subjects. Less common in women, the pathology has the same clinical translation as in men.