Glucose Phosphate Isomerase Deficiency

At a glance

Glucose phosphate isomerase deficiency is the third most common red blood cell glycolytic enzymopathy after glucose-6-phosphate isomerase deficiency and pyruvate kinase deficiency. It is an autosomal recessive disease caused by a deficiency in the enzyme glucose phosphate isomerase and clinically characterized by nonspherotic hemolytic anemia and spontaneous hemolytic crises. Approximately 50 different cases have been described to date. Associated with mild to severe chronic hemolytic anemia in homozygotes or compound heterozygotes.

Synonyms

Phosphohexose Isomerase Deficiency; Autocrine Motility Factor Deficiency.

Incidence

Glucose Phosphate Isomerase deficiency is the third most common enzymopathy (after Glucose-6-Phosphate Dehydrogenase Deficiency and Pyruvate Kinase Deficiency) that results in mild to severe hemolytic anemia.

Genetic inheritance

This autosomal dominant disorder (19cenq12) is most symptomatic in cases presenting homozygous or compound heterozygous pattern.

Pathophysiology

The enzyme glucose phosphate isomerase catalyzes the interconversion of the second step of the Embden-Meyerhof (glucose metabolism) pathway into fructose-6-phosphate. This enzyme is known as the rate-limiting factor in the mitochondrial energy pathway.

Clinical aspects

Patients present with nonspherocytic mild to severe hemolytic anemia, most often as spontaneously occurring crises. Jaundice, splenomegaly, and cholecystitis are often associated. Muscle weakness is reported. The cardiovascular system is not affected. Neurologically, the presence of mental retardation and mixed sensory and cerebellar ataxia is noted.

Precautions before Anesthesia

Preoperatively, a complete laboratory assessment should be conducted to confirm the presence of phosphohexose isomerase deficiency (essential to the risk of spontaneous hemolytic crises) and evaluate the level of red cell osmotic fragility. The patient’s hematocrit should be obtained.

Anesthetic considerations

The presence of reduced leukocyte superoxide anion production should raise the concern of infection because of reduced leukocyte bactericidal activity. Patients appear to respond positively to splenectomy. Proper evaluation for the need of blood preoperatively will be required and the blood bank informed of the potential needs for blood transfusion. In some cases a splenectomy may improve the anemia.

Other conditions to be considered

• ☞Chronic Hexokinase Deficiency Hemolytic Anemia: Autosomal recessive inherited disease characterized by chronic hemolytic anemia associated with severe deficiency of red cell glucose phosphate isomerase. Some cases of autosomal dominant transmission have been reported. Like phosphofructokinase and pyruvate kinase, the hexokinase enzyme is a rate-limiting factor in the metabolism of glucose in the Embden-Meyerhof pathway. Because glycolysis is the only source of energy for the red cells, deficiency in hexokinase results in chronic hemolytic anemia. Few allelic variants have been described of the chronic form. Fukuoka variant: Reported in the Japanese literature as the association of chronic glucose phosphate deficiency and a history of prolonged neonatal jaundice. Iwate variant: Chronic form of ...