The mystery of 'saturation gap' and falsely normal G6PD: a case of primaquine-induced haemolysis in Plasmodium vivax malaria infection

Eradication therapy in Plasmodium vivax in variants of glucose-6-phosphate dehydrogenase (G6PD) deficiency individuals remains a clinical challenge. We present a case of primaquine-induced methaemoglobinaemia and haemolytic anaemia in a patient with falsely normal qualitative G6PD result during initial presentation, which was complicated with clinical sequelae of thrombosis. Further investigations showed moderate degree of G6PD deficiency. Our patient responded well to vitamin C and a modified weekly regimen of primaquine with no evidence of malaria relapse.

Automated summary

Eradication therapy in Plasmodium vivax in variants of glucose-6-phosphate dehydrogenase (G6PD) deficiency individuals remains a clinical challenge, with potential complications such as primaquine-induced methaemoglobinaemia and haemolytic anaemia. Close monitoring and adjustment of drug treatment are necessary to manage these risks effectively.