From the Guidelines
G6PD deficiency is associated with an increased risk of hemolysis when treated with certain antimalarial medications, such as primaquine and tafenoquine, and therefore requires cautious management in the context of malaria treatment. The relationship between G6PD deficiency and malaria is complex, with G6PD deficiency providing partial protection against malaria, particularly Plasmodium falciparum infection, as it creates an inhospitable environment for malaria parasites within red blood cells 1. However, G6PD-deficient individuals can still contract malaria, and the use of antimalarial medications like primaquine and tafenoquine can trigger hemolytic crises in these patients.
Key Considerations
- G6PD testing is recommended before administering primaquine or tafenoquine to patients with suspected or confirmed malaria 1.
- Alternative antimalarials like chloroquine, artemisinin-based combinations, or atovaquone-proguanil are generally safer options for G6PD-deficient individuals requiring malaria treatment or prophylaxis 1.
- The risk of hemolysis in G6PD-deficient individuals can be mitigated by using primaquine at a lower dose (45 mg once weekly) for 8 weeks in patients with mild to moderate G6PD deficiency (>30 < 70% activity) 1.
Management of Malaria in G6PD-Deficient Individuals
- G6PD-deficient individuals should be tested for G6PD deficiency before receiving antimalarial medications like primaquine or tafenoquine.
- Treatment of malaria in G6PD-deficient individuals should be guided by the severity of the deficiency and the specific antimalarial medication used.
- Close monitoring for signs of hemolysis is essential in G6PD-deficient individuals receiving antimalarial treatment.
From the Research
Relationship between G6PD Deficiency and Malaria
- G6PD deficiency is relatively common in populations exposed to malaria, and it appears to provide some protection from this infection 2.
- However, G6PD deficiency can also cause hemolysis after administration of some antimalarial drugs, especially primaquine 3, 2, 4.
- The risk of drug-induced G6PD deficiency-related hemolysis depends on several factors, including the G6PD variant, the drug and drug dosage schedule, patient status, and disease factors 2.
Prevalence of G6PD Deficiency in Malaria Patients
- Studies have reported varying prevalence rates of G6PD deficiency in malaria patients, ranging from 9.0% to 33.75% 3, 5.
- A study conducted in six African countries found that 9.0% of malaria patients had G6PD deficiency, with 7.2% being male hemizygous and 1.8% being female homozygous 5.
- Another study conducted in North East India found that 33.75% of patients with vivax malaria had G6PD deficiency, with the majority having the G6PD B genotype 3.
Impact of Malaria on G6PD Activity
- Malaria can cause hemolysis, leading to the replacement of older erythrocytes with low G6PD activity by reticulocytes and young erythrocytes with higher activity 6.
- A study found that G6PD activity rose significantly during acute malaria, with 66.7% of severely deficient participants and 87.2% of participants with intermediate deficiency having normal activities when presenting with malaria 6.
Implications for Malaria Treatment
- The use of primaquine, a mainstay in the treatment of vivax malaria, is contraindicated in patients with G6PD deficiency due to the risk of hemolysis 3, 4.
- Screening for G6PD deficiency is recommended before administering primaquine to patients with vivax malaria, especially in areas where G6PD deficiency is prevalent 3, 4.