G6PDpuutos

G6PDpuutos, known in English as glucose-6-phosphate dehydrogenase deficiency, is an inherited enzymopathy characterized by reduced activity of the G6PD enzyme in red blood cells. The condition compromises the cell's ability to protect against oxidative stress, making hemoglobin susceptible to denaturation and leading to hemolysis under stress.

Genetics and epidemiology: It is an X-linked recessive trait. Males are typically affected; females can be affected if homozygous or if X-inactivation is skewed. Prevalence varies widely by ethnicity, being more common in Mediterranean, Middle Eastern, African, and Southeast Asian populations. Heterozygous carriers may have mild or no symptoms. Some protection against severe malaria has been proposed for carriers.

Clinical features: Many individuals are asymptomatic. Symptoms can appear after hemolysis and include fatigue, pallor, back or abdominal pain, dark urine, and jaundice. Neonatal jaundice is common in infants with G6PD deficiency.

Triggers: Fava beans and certain medicines (such as primaquine, sulfamethoxazole/trimethoprim, nitrofurantoin, dapsone, methylene blue, chloroquine) can precipitate acute hemolysis. Infections can also trigger episodes. Avoidance of triggers is a key part of management.

Diagnosis: Screening can be performed in newborns. Diagnostic tests measure G6PD enzyme activity in red blood cells, using methods such as fluorescent spot tests or spectrophotometric assays; genetic testing can identify specific mutations. Diagnosis in females can be more complex due to mosaicism.

Management and prognosis: There is no cure; management focuses on avoiding triggers, promptly stopping any implicated drugs during a hemolytic episode, and treating complications (hydration, transfusion if needed). Regular follow-up and genetic counseling are recommended. With trigger avoidance, most individuals lead normal lives, though severe hemolysis can be life-threatening if not treated.