Membrane 156 Glucose-6-Phosphate Dehydrogenase Deficiency

Hemolytic anemia results from decreased RBC survival time due to destruction in the spleen or circulation. The most common etiologies are RBC membrane defects (e.g., hereditary spherocytosis), altered Hb solubility or stability (e.g., sickle cell anemia [see Chap. 34] and thalassemias), and changes in intracellular metabolism (e.g., glucose-6-phosphate dehydrogenase deficiency). Some drugs cause direct oxidative damage to RBCs (see Appendix 3). 

Although ABO incompatibility and Rh-anti-body formation are the most common causes of hemolysis, other causes need to be considered, such as cephalohematoma formation during delivery with resultant increase in bilirubin production as the hematoma is resorbed hereditary spherocytosis, which is a red cell membrane defect that results in premature breakdown of the red cells and glucose 6-phosphate dehydrogenase deficiency, which is involved in maintaining adequate reduced glutathione levels in the red cell. Infection in the neonatal period is uncommon but still must be considered as a cause of jaundice. In particular, infections of the urinary tract lead frequently to jaundice as a preliminary symptom. The increase in infection associated with instrumentation in the premature infant is always a concern. 

Glutathione also maintains the integrity of red cells by reacting with peroxides that would otherwise degrade fatty-acid side chains in the ceU membrane. About 11% of African-Americans are affected by glucose-6-phosphate dehydrogenase deficiency. 

Erythrocyte membrane abnormalities in glucose-6-phosphate dehydrogenase deficiency of the Mediterranean and A-types. 

Red cell membrane protein in thalassemia and glucose-6-phosphate dehydrogenase deficiency anemia. 

Figure 20.25. Red Blood Cells with Heinz Bodies. The light micrograph shows red blood cells obtained from a person deficient in glucose 6-phosphate dehydrogenase. The dark particles, called Heinz bodies, inside the cells are clumps of denatured protein that adhere to the plasma membrane and stain with basic dyes. Red blood cells in such people are highly susceptible to oxidative damage. [Courtesy of Dr. Stanley Schrier.]...

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