Diagnosis of red cell G6PD deficiency in rural Burkina Faso: comparison of a rapid fluorescent enzyme test on filter paper with polymerase chain reaction based genotyping.

Glucose-6-phosphate dehydrogenase (G6PD) deficient individuals are at increased risk of developing haemolysis following treatment with various antimalarial drugs. Reliable field tests for G6PD deficiency are thus needed in chemotherapy studies and their validity has to be assessed. In two phase II clinical trials on methylene blue (MB) antimalarial therapy in rural Burkina Faso, paediatric and adult participants were tested for G6PD deficiency. The results of a haemoglobin-adjusted nicotinamide adenine dinucleotide phosphate (NADPH) fluorescence test on paper (NFP test) were compared with polymerase chain reaction (PCR)-based G6PD genotyping also using blood samples on filter papers. This is the first study comparing sensitivity and specificity of the two methods. There was good agreement between the NFP test results and the PCR findings. The estimate of the sensitivity of the NFP test was 98.2% (95.8-99.6%) and the specificity was 97.1% (94.2-99.2%). In conclusion, the NFP assay is a reliable and inexpensive method for large-scale G6PD deficiency screening in rural West Africa.