New nutritional challenge in glucose-6-phosphate dehydrogenase-deficient patients: Prospective study with genotype–phenotype correlation

Abstract

Abstract Objectives Glucose-6-phosphate dehydrogenase (G6PD) deficiency adds a burden on patients and their families in Egypt and Middle East due to lifelong diet restriction. Thus, the current study aimed to investigate the challenge with non-fava beans (dicotyledons) diet on the development of hemolysis in G6PD-deficient patients as well as making a genotype–phenotype correlation from two centers. Patients and methods A 1-year interventional study was registered in the Clinical Trials Government (NCT02498340), including 108 patients subjected to quantitative analyses for enzymatic activity and molecular typing of G6PD enzyme using a PCR-amplification refractory mutation system technique. Dietetic challenge included ingestion of non-fava beans diet taken in small amount (10–20 g/day for 3 successive days/week) weekly for 1 year with clinical and laboratory follow-up of essential markers of hemolysis. Results Mediterranean mutation was the commonest type (53.7%) and with significantly more patients with severe enzyme deficiency in this mutation, followed by African mutation (16.7%), while Cairo mutation was expressed in 13.9%. All studied genotypes were comparable regarding their clinical presentations. After diet challenge, none of the patients with identified genotypes showed significant changes in their G6PD, mean hemoglobin, indirect bilirubin levels, and reticulocytic count (%) compared with baseline. Conclusion G6PD Mediterranean mutation is the commonest mutations causing G6PD deficiency in Egypt. G6PD-deficient children might tolerate diet that contains a small amount of non-fava beans for 1 year without inducing hemolysis, so its restriction in G6PD-deficient patients should be reconsidered.