Glucose-6-phosphate deficiency

Oxygen is normally readily available to all reasonably well-perfused tissues, but deep inside organs such as the liver, especially the centrilobular area (see chap. 6), there will be a reduction in the oxygen concentration. This is clearly important when both oxidative and reductive pathways are available for a particular substrate. Therefore, as conditions in a particular tissue become more anaerobic, reductive pathways will become more important. This is well illustrated by the metabolism of halo thane where, in the rat, hypoxia will increase reductive metabolism and hepa to toxicity (see chap. 7). Glutathione is an extremely important cofactor, involved in both protection and conjugation. It may be depleted by both of these processes, or under certain circumstances, such as hereditary glucose-6-phosphate deficiency in man, supply may be reduced (see chap. 5). This will clearly influence toxicity, and there are a number of examples discussed in chapter 7 in which it is important. 

Hematologic Megaloblastic anemia, leukopenia, and thrombocytopenia may occur all of these effects may be reversed by the concurrent administration of folinic acid (see p. 379), which protects the patient and does not enter the microorganism. Hemolytic anemia may occur in patients with glucose-6-phosphate deficiency due to the sulfamethoxazole (see p. 351). 

The gene of glucose-6-phosphate dehydrogenase is carried on the X chromosome. The female has two X chromosomes, but the gene stored in only one of them is expressed. Therefore, there are two populations of red cells in victims of glucose-6-phosphate deficiency one that carries the deficiency and another that is normal. This rare situation has been taken advantage of for the study of tumor origin. 

B9. Baronciani, L., Zanella, A., Bianchi, P Zappa, M Alfinito, E, Iolascon, A., Tannoia, N., Beutler, E., and Sirchia, G., Study of the molecular defects in glucose phosphate isomerase-deficient patients affected by chronic hemolytic anemia. Blood 88,2306-2310 (1996). 

FI 3. Fujii, H., Kanno, H Hirono, A., and Miwa, S., Hematologically important mutations Molecular abnormalities of glucose phosphate isomerase deficiency. Blood Cells Mol. Dis. 22,96-97 (1996). 

XI. Xu, W. M., and Beutler, E The characterization of gene mutations for human glucose phosphate isomerase (GPI) deficiency associated with chronic hemolytic anemia. J. Clin. Invest. 94, 2326-2329 (1994). 

D-2) Glucose phosphate isomerase deficiency. Associated with a hemolytic anemia. 

D-Glucose PGI1 mutant is deficient in D-glucose phosphate isomerase 344... 

Deficiency of glucose phosphate isomerase (GPI) has been associated with chronic hemolytic disease in a few dozen reported cases and may also cause hemolytic disease of the newborn. Although the third most frequently reported enzymopathy causing hemolytic disease, it has been quite rare in our experience. 

Hutton 11, Chilcote RR. Glucose phosphate isomerase deficiency with hereditary nonspherocytic hemolytic anemia. 1 Pediatr 1974 85 494-7. 

Ravindranath Y, Paglia DE, Warrier I, Valentine W, Nakatani M, Brockway RA. Glucose phosphate isomerase deficiency as a cause of hydrops fetalis. N Engl J Med 1987 316 258-61. 

Combined glucose phosphate isomerase and glucose-6-phosphate dehydrogenase deficiency of eiythroc5d es. 

Favism is the haemolysis obseived after eating Vica fava. This reaction is observed in individuals with glucose-6-phosphate dehydrogenase deficiency. This common deficiency is also responsible for haemolysis in response to the antimalarial drug primaquine and others. 

An idiosyncratic reaction is a harmful, sometimes fatal reaction, that occurs in a small minority of individuals. The reaction may occur with low doses of drags. Genetic factors may be responsible, e.g. glucose-6-phosphate dehydrogenase deficiency, although the cause is often poorly understood. 

Glucose- 6-phosphate dehydrogenase Low or absent enzyme activity in about 10% of African populations. Hemolysis following intake of a number of drugs which have electrophilic reactive metabolites, but also, carriers of this enzyme deficiency have a partial protection from malaria. 

Genetic deficiency of glucose-6-phosphate dehydrogenase, with consequent impairment of the generation of NADPH, is common in populations of Mediterranean and Afro-Caribbean origin. The defect is manifested as red cell hemolysis (hemolytic anemia) when susceptible individuals are subjected to oxidants, such as the an-timalarial primaquine, aspirin, or sulfonamides or when... 

Glucose-6-phosphate dehydrogenase (G6PD) deficiency (MIM 305900) A variety of mutations in the gene (X-linked) for G6PD, mostly single point mutations... 

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