Biochemical Estimation of Glucose 6 Phosphate Dehydrogenase Deficiency in Saudi Adults: Different Methods and Its Rationalization

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy affecting 400 million people, globally. G6PD deficiency is an X-linked genetic condition, which is more likely to affect males than females. Heterozygous females go undetected in a commonly used method. The aim of the study was to identify & rationalize different biochemical methods for detections of G6PD deficiency. Methods: Cross section retrospective study was conducted on 1584 (800 males, 784 females) blood samples collected from King Abdulaziz University Hospital (KAUH) and King Fahd Armed force hospital (KFAFH) in Jeddah, Western Saudi Arabia. Blood samples were screened for G6PD activity by fluorescence spot test, semi quantitative color reduction test and spectrometric quantitative evaluation. Hemoglobin (Hb) was measured on the same sample by BC-3200 Auto hematology Analyser. G6PD activity was recorded as U/g Hb. Samples identified as deficient with cutoff ≤4.6 U/gHb. Results: The prevalence of G6PD deficiency identified by fluorescence spot test was 73(4.6%) and all were deficient male. By semi quantitative method, the prevalence rate was 51(3.2%) and again all were male deficit patients. However, when quantitative spectrometric method was used, the prevalence was found in 90(5.7%), where in 73(4.6%) deficient patients were males and 17(1.1%) were females. Conclusion: Since the fluorescence spot test did not miss any G6PD deficient male, it should be restricted to males and quantitative test should be done on females. Each ethnic group should cultivate their own cutoff value for categorization of deficient patients. Corresponding author.