Acquired glucose 6-phosphate dehydrogenase (G6PD) deficiency in a patient with Chronic Myelomonocytic Leukemia

Clonal hematopoiesis and acquired genetic abnormalities of the red cell: An historical review

Several syndromes affecting the red cell that mimic those induced by germline mutations may result from a somatic mutation that accompanies a myeloid malignancy. These syndromes are most notable in cases of myelodysplastic syndrome, but they are not limited to any one category of myeloid neoplasm. Their occurrence in males exceed the male predominance that is evident in myeloid neoplasms. The syndromes include disorders of globin chain synthesis (α- and β-thalassemia), heme synthesis (erythropoietic porphyria and erythropoietic uroporphyria), red cell membrane structure (elliptocytosis and spherocytosis), red cell enzyme activity (pyruvate kinase deficiency, glucose-6-phosphate dehydrogenase deficiency) and lowered expression of red cell ABO blood group antigens. This historical review describes the path to uncovering these acquired syndromes and their causal somatic mutations, where known. These syndromes often go unrecognized because of the dominant concern of the primary neoplasm. They may add to the healthcare needs of the patient.

Acquired Glucose-6-Phosphate Dehydrogenase Deficiency

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a hereditary condition caused by mutations on chromosome X and is transmitted by a sex-linked inheritance. However, impairment of G6PD activity may result from biochemical mechanisms that are able to inhibit the enzyme in specific clinical conditions in the absence of a structural gene-level defect. In this narrative review, a number of clinical settings associated with an "acquired" G6PD deficiency, phenotypically undistinguishable from the primary deficiency, as well as the mechanisms involved, were examined. Hyperaldosteronism and diabetes are the most common culprits of acquired G6PD deficiency. Additional endocrine and metabolic conditions may cause G6PD deficiency in both hospitalized and outpatients. Contrary to the inherited defect, acquired G6PD deficiency is a condition that is potentially curable by removing the factor responsible for enzyme inhibition. Awareness regarding acquired G6PD deficiency by physicians might result in improved recognition and treatment.