Glucose 6 Phosphate dehydrogenase deficiency

Glucose 6 Phosphate dehydrogenase deficiency

Abnormalities in the hexose monophosphate shunt or glutathione metabolism resulting from deficient or impaired enzyme function reduce the ability of red cells to protect themselves against oxidative injuries. This results in hemolyic disease. The most important of these is G6PD deficiency. Normal G6PD functioning is required to decrease oxidative damage to RBCs.
The key manifestation of G6PD deficiency is acute intravascular hemolysis after exposure to oxidant stress. Oxidative stress may occur due to food like fava beans, infections and oxidant drugs like antimalarials and sulphonamide.
Acute intravascular hemolysis presents with anemia, hemoglobinemia and hemoglobinuria usually 2-3 days following exposure of G6PD deficient individuals to oxidants. The oxidative stress also results in oxidation of haemoglobin to form Heinz bodies. These heinz bodies may cause damage to the cell wall of the RBCs resulting in intravascular hemolysis. If this doesn’t happen, what happens is that when they come in contact with the reticuloendothelial system, the macrophages try to bite the Heinz bodies away resulting in Bite cells. And inturn extravascular hemolysis. Since only older red cells are at risk of lysis the episode is self-limited as hemolysis stops when only younger rbcs remain. Reticulocytosis is seen in the recovery phase. The features of chronic hemolyic anemias like splenomegaly and cholelithiasis are absent because the haemolytic episodes occur intermittently