Phosphoglycerate Kinase Deficiency

At a glance

A rare congenital enzymatic defect in glycolysis process. It is characterized by various combinations of nonspherocytic hemolytic anemia, neurological dysfunctions, and myopathies.

Synonym

Glycogenosis Type X.

Genetic inheritance

X-linked recessive.

Pathophysiology

Phosphoglycerate kinase (PK) catalyzes the interconversion of 3-phosphoglycerate and 1,3-diphosphoglycerate with the production of adenosine triphosphate (ATP). The enzyme is encoded by a gene located on Xq13.3. At least 20 different mutations have been described thus far in the PKG1 gene. These variants of the disease have differing involvement of red cells, muscle, and central nervous system (CNS). This could be a result of organ-specific isoenzymes being affected differently by the mutation(s).

Diagnosis

Chronic hemolytic anemia, occasional hemoglobinuria; phosphoglycerokinase activity low (<5%) in muscle cells or RBCs. Normal muscle biopsy.

Clinical aspects

Hemolytic anemia, mental retardation, and myopathy may coexist or manifest in various combinations. Neonatal period: nonimmune hydrops, jaundice, hepatomegaly, hemolytic anemia. Childhood: mild mental retardation (delayed language), behavioral problems, seizures. Adolescence and Adulthood: nonspherocytic hemolytic anemia; exercise-induced cramps, myalgia, and rhabdomyolysis; myoglobinuria after vigorous exercise.

Precautions before anesthesia

Check hemoglobin level; a long preoperative fasting time should be avoided.

Anesthetic considerations

Monitor blood glucose level; in case of rhabdomyolysis, ensure increased diuresis with IV mannitol and intravascular fluid.

Pharmacological implications

Avoidance of succinylcholine because of the risk of rhabdomyolysis.

References