| Summary: | Primaquine and tafenoquine are the only licensed drugs with activity against Plasmodium
vivax hypnozoites but cause haemolysis in patients with glucose–6–phosphate dehydrogenase (G6PD) deficiency. Malaria also causes haemolysis, leading to the replacement of
older erythrocytes with low G6PD activity by reticulocytes and young erythrocytes with
higher activity. Aim of this study was to assess the impact of acute malaria on G6PD activity.
Selected patients with uncomplicated malaria were recruited in Bangladesh (n = 87), Indonesia (n = 75), and Ethiopia (n = 173); G6PD activity was measured at the initial presentation
with malaria and a median of 176 days later (range 140 to 998) in the absence of malaria.
Among selected participants (deficient participants preferentially enrolled in Bangladesh but
not at other sites) G6PD activity fell between malaria and follow up by 79.1% (95%CI: 40.4
to 117.8) in 6 participants classified as deficient (<30% activity), 43.7% (95%CI: 34.2 to
53.1) in 39 individuals with intermediate activity (30% to <70%), and by 4.5% (95%CI: 1.4 to
7.6) in 290 G6PD normal (�70%) participants. In Bangladesh and Indonesia G6PD activity
was significantly higher during acute malaria than when the same individuals were retested
during follow up (40.9% (95%CI: 33.4–48.1) and 7.4% (95%CI: 0.2 to 14.6) respectively),
whereas in Ethiopia G6PD activity was 3.6% (95%CI: -1.0 to -6.1) lower during acute
malaria. The change in G6PD activity was apparent in patients presenting with either
P. vivax or P. falciparum infection. Overall, 66.7% (4/6) severely deficient participants and
87.2% (34/39) with intermediate deficiency had normal activities when presenting with
malaria. These findings suggest that G6PD activity rises significantly and at clinically relevant levels during acute malaria. Prospective case-control studies are warranted to confirm the degree to which the predicted population attributable risks of drug induced haemolysis is
lower than would be predicted from cross sectional surveys.
|
|---|