Inherited, non-spherocytic haemolysis due to deficiency of glucose-6-phosphate dehydrogenase.

The about 400 million individuals worldwide suffering from a hereditary deficiency of the enzyme glucose-6-phosphate dehydrogenase (G6PD) may experience different degrees of haemolytic anaemia. Haemoglobin is present in very high concentrations in the erythrocyte cytoplasm, at risk of falling out of solution if the internal environment or the haemoglobin itself is changed. G6PD is a crucial enzyme producing reduced glutathione in the erythrocyte cytoplasm for the purpose of protecting haemoglobin against oxidative damage. The presence of unopposed oxidizing agents leading to oxidation of the sulfhydryl bridges between parts of the haemoglobin molecule decrease the solubility of haemoglobin, leading to precipitations called Heinz bodies. The laboratory investigation of G6PD deficiency is commonly done by a quantitative spectrophotometric analysis or by a rapid fluorescent spot test detecting the generation of NADPH from NADP. Genetic tests based on polymerase chain reaction detect specific mutations and may be used for population screening, family studies, or prenatal diagnosis.