Validating the assessment of glucose 6 phosphate dehydrogenase g6pd
The most widely applied technology for G6PD screening-the fluorescent spot test (FST)-is impractical in that setting.We evaluated a new point-of-care G6PD screening kit (Care Start G6PD, CSG) against FST using graded Cu Cl treatments to simulate variable hemizygous states, and varying proportions of Cu Cl-treated RBC suspensions to simulate variable heterozygous states of G6PD deficiency.The CSG test costs less, requires no specialized equipment, laboratory skills, or cold chain for successful application, and performs as well as the FST standard of care for G6PD screening.
We optimized Cu Cl inhibition of G6PD in normal red blood cells (RBCs) to assess G6PD diagnostic technologies suited to point of care in the impoverished rural tropics.Then, 10 μL of whole blood collected in acid citrate dextrose (ACD) tubes (BD Vacutainer ACD Solution A; Becton-Dickinson) was added to the 3 m L mixture.The tube was incubated at 30°C for 5 minutes and its absorbance at 340 nm wavelength was measured on an ultraviolet spectrophotometer (Biowave II; Biochrome) and recorded as “initial” absorbance optical density.Although long viewed as a relatively benign infection, reports and studies from endemic areas and in travelers over the past decade reveal an often pernicious and sometime fatal course associated with a diagnosis of vivax malaria.
This understanding has focused renewed emphasis and interest on long-neglected clinical and public health issues regarding this infection, especially the very difficult problem of glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine therapy.
Failure to prevent relapse in vivax malaria results in very high risk of debilitating illness of deepening seriousness and opportunities for onward transmission to others.