Screening for Glucose-6-Phosphate Dehydrogenase Deficiency Using Three Detection Methods: A Cross-Sectional Survey in Southwestern Uganda.

Despite the potential benefit of primaquine in reducing Plasmodium falciparum transmission and radical cure of Plasmodium vivax and Plasmodium ovale infections, concerns over risk of hemolytic toxicity in individuals with glucose-6-phosphate dehydrogenase deficiency (G6PDd) have hampered its deployment. A cross-sectional survey was conducted in 2014 to assess the G6PDd prevalence among 631 children between 6 and 59 months of age in southwestern Uganda, an area where primaquine may be a promising control measure. G6PDd prevalence was determined using three detection methods: a quantitative G6PD enzyme activity assay (Trinity Biotech® G-6-PDH kit), a qualitative point-of-care test (CareStart™ G6PD rapid diagnostic test [RDT]), and molecular detection of the G6PD A- G202A allele. Qualitative tests were compared with the gold standard quantitative assay. G6PDd prevalence was higher by RDT (8.6%) than by quantitative assay (6.8%), using a < 60% activity threshold. The RDT performed optimally at a < 60% threshold and demonstrated high sensitivity (≥ 90%) and negative predictive values (100%) across three activity thresholds (below 60%, 30%, and 40%). G202A allele frequency was 6.4%, 7.9%, and 6.8% among females, males, and overall, respectively. Notably, over half of the G202A homo-/hemizygous children expressed ≥ 60% enzyme activity. Overall, the CareStart™ G6PD RDT appears to be a viable screening test to accurately identify individuals with enzyme activities below 60%. The low prevalence of G6PDd across all three diagnostic modalities and absence of severe deficiency in our study suggests that there is little barrier to the use of single-dose primaquine in this region.