Pyruvate Kinase Deficiency


Pyruvate Kinase Deficiency

Pyruvate kinase (PK) deficiency is one of the most common enzymatic defects of the RBCs, it manifests clinically as a hemolytic anemia that can range from mild to severe.

Pyruvate kinase (PK) deficiency is inherited in an autosomal recessive pattern.

The birth history of patients with pyruvate kinase deficiency includes severe anemia, severe jaundice, kernicterus, and a history of exchange transfusion.

Clinical features:

There may be moderate or even severe hemolytic anemia (read more about hemolytic anemias )

Mild to severe anemia (normocytic or macrocytic)

Reticulocytosis

Growth delay

Failure to thrive

Gall bladder stones: Usually after the first decade of life but possibly in childhood

Frontal bossing

Hyperbilirubinemia in the newborn

Jaundice

Mild to moderate splenomegaly

Upper-right-quadrant tenderness

Chronic leg ulcers (adults)

Diagnosis:

FBC

Differential blood count

Reticulocyte count

Serum bilirubin

Direct Coomb’s test (to exclude immune hemolysis)

Peripheral blood film examination

Normoblastic erythroid hyperplasia of the bone marrow

Extramedullary hematopoiesis

The enzyme activity rate in most patients with pyruvate kinase deficiency is 5-25% of normal.

PK deficiency in splenectomized child

Peripheral blood smear in a child with splenectomy and pyruvate kinase deficiency

Treatment:

  • In patients with mild to moderate pyruvate kinase deficiency, care is predominantly supportive.
  • Red blood cell transfusion may be necessary if the anemia is significant.
  • Folic acid supplements.
  • Splenectomy is indicated only for patients with severe anemia.

References:

Hassan M Yaish, MD. Pyruvate Kinase Deficiency: Practice Essentials, Background, Pathophysiology http://emedicine.medscape.com/article/2196589-overview Accessed: April 2014.

Abdel Fattah M, Abdel Ghany E, Adel A, Mosallam D, Kamal S. Glucose-6-phosphate dehydrogenase and red cell pyruvate kinase deficiency in neonatal jaundice cases in Egypt. Pediatr Hematol Oncol. 2010 May. 27(4):262-71.

Leave a Reply

Your email address will not be published. Required fields are marked *