Pyruvate kinase deficiency

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Pyruvate Kinase Deficiency is an inherited autosomal recessive genetic disorder which affects the survival of red blood cells. A variety of mutations can lead to lowered production, activity, or stability of pyruvate kinase, an enzyme essential to glycolysis. A total lack of this enzyme's activity will be lethal. Because the ability of erythrocytes to manufacture ATP depends on glycolysis, the cells become deficient in energy and unable to maintain the activity of the basolateral Na/K ATPase. This will result in an increase in intracellular [K+] which will cause water to diffuse passively into the red blood cell (RBC) and will lead to swelling. This swelling will lead to lysis of the RBCs and an increase in plasma bilirubin. The increase in plasma bilirubin will lead to jaundice and the lysis of the RBCs will lead to hemolytic anemia. The buildup of reaction intermediates can also increase the level of 2,3-bisphosphoglycerate in the cells and affect tissue oxygenation. This will cause a "right shift" in the hemoglobin oxygen saturation curve, implying a decreased oxygen affinity for the hemoglobin and earlier oxygen unloading than under normal conditions.

Clincally, this disorder is most common glycolytic enzyme deficiency, that will lead to hemolytic anemia.

[edit] Treatment

Treatment can include a blood transfusion or removal of the spleen. Treatment is usually effective in reducing the severity of the symptoms.