G6PD Deficiency (Chronic Management)
A 10-year-old boy presents two days after pallor, dark urine and jaundice began hours after a meal of fava beans. His maternal uncle has had identical episodes since childhood. Haemoglobin is 9.6 g/dL, reticulocytes 7%, the direct antiglobulin test is negative, and the blood film shows bite cells and Heinz bodies. He is stable and the haemoglobin is rising. Which is the most appropriate long-term therapy?
- A.Daily folic acid supplementationCorrect
- B.Daily oral iron supplementation
- C.Monthly vitamin B12 injections
- D.Scheduled red cell transfusions every 4 weeks
Explanation
The bite cells, Heinz bodies, negative direct antiglobulin test and a fava bean trigger in a boy with an affected maternal uncle establish X-linked glucose-6-phosphate dehydrogenase deficiency. The mainstay of long-term care is avoidance of oxidant triggers, in particular fava beans, sulfonamides, nitrofurantoin, dapsone, primaquine, methylene blue and naphthalene mothballs, together with prompt treatment of infections, which are themselves a common precipitant. Because ongoing and episodic haemolysis increases red cell turnover, folate consumption rises and daily folic acid supplementation is recommended to prevent a superimposed megaloblastic anaemia in patients with chronic haemolytic states. Iron is contraindicated as routine therapy: haemolysis releases iron rather than losing it, and unnecessary supplementation risks iron overload. Vitamin B12 deficiency is unrelated to haemolysis and would present with macrocytosis and neurological features, not with an oxidant-triggered crisis. Regular transfusion programmes belong to transfusion-dependent disorders such as beta thalassaemia major; in G6PD deficiency transfusion is reserved for severe acute haemolysis, generally when the haemoglobin falls to about 6 g/dL or below or when the child is haemodynamically unstable or has ongoing brisk intravascular haemolysis. This boy is stable with a recovering haemoglobin, so transfusion is not indicated and counselling plus folate is the correct plan.
Why each option
- A.
- Correct. Increased red cell turnover raises folate demand, so daily folic acid is given alongside strict avoidance of fava beans and oxidant drugs.
- B.
- Haemolysis liberates iron rather than depleting it; routine iron risks overload and does not treat the deficiency.
- C.
- Vitamin B12 deficiency causes megaloblastic and neurological disease and has no role in oxidative haemolysis.
- D.
- Regular transfusion is for transfusion-dependent disorders; in G6PD deficiency it is reserved for severe or haemodynamically significant acute haemolysis.
Reference: UpToDate 2025, Glucose-6-phosphate dehydrogenase (G6PD) deficiency: Treatment and prevention
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