Erythrocytes deficient in glucose-6-phosphate dehydrogenase (G6PD) is more susceptible to oxidative damage from free radical derived compounds. The hemolysis triggered by oxidative agents such as primaquine (PQ) is used for the radical treatment of hypnozoites of P. vivax. Testing of G6PD screening before malaria treatment is not a common practice in Thailand, which poses patients at risk of hemolysis. This retrospective study aimed to investigate the prevalence of G6PD in malaria patients who live in Southern Thailand. Eight hundred eighty-one malaria patients were collected for 8-year from 2012 to 2019, including 785 (89.1%) of P. vivax, 61 (6.9%) of P. falciparum, 27 (3.1%) of P. knowlesi, and 8 (0.9%) of mixed infections. The DiaPlexC genotyping kit (Asian type) and PCR-RFLP were employed to determine the G6PD variants. The result showed that 5 different types of G6PD variants were identified in 26 cases (2.9%); 12/26 (46.2%) had Mahidol (487G>A) and 11/26 (42.3%) had Viangchan (871G>A) variants, while the rest had Kaiping (1388G>A), Union (1360C>T), and Mediterranean (563C>T) variants. G6PD Songklanagarind (196T>A) variant was not found in the study. Our result did not show a significant difference in the malaria parasite densities in patients between G6PD-deficient and G6PD-normal groups. According to our findings, testing G6PD deficiency and monitoring the potential PQ toxicity in patients who receive PQ are highly recommended.
Keywords: G6PD; P. vivax; Southern Thailand; malaria.