Impact of Glucose‐6‐phosphate Dehydrogenase Deficiency on Sickle Cell Anaemia Expression in Infancy and Early Childhood: a Prospective Study

In patients with sickle cell anaemia (SCA), concomitant glucose‐6‐phosphate dehydrogenase (G6PD) deficiency is usually described as having no effect and only occasionally as increasing severity. We analysed sequential clinical and biological data for the first 42 months of life in SCA patients diagnosed by neonatal screening, including 27 G6PD‐deficient patients, who were matched on sex, age and parents' geographic origin to 81 randomly selected patients with normal G6PD activity. In the G6PD‐deficient group, steady‐state haemoglobin was lower (−6·2 g/l, 95% confidence interval (CI), [−10·1; −2·3]) and reticulocyte count higher (247 × 109/l, 95%CI, [97; 397]). The acute anaemic event rate was 3 times higher in the G6PD‐deficient group (P < 10−3). A higher proportion of G6PD‐deficient patients required blood transfusion (20/27 [74%] vs. 37/81 [46%], P < 10−3), for acute anaemic events, and also vaso‐occlusive and infectious events. No significant between‐group differences were found regarding the rates of vaso‐occlusive, infectious, or cerebrovascular events. G6PD deficiency in babies with SCA worsens anaemia and increases blood transfusion requirements in the first years of life. These effects decrease after 2 years of age, presumably as the decline in fetal haemoglobin levels leads to increased sickle cell haemolysis and younger red blood cells with higher G6PD activity.