pyruvate kinase (PK) deficiency


A glycolytic defect --> congenital non-spherocytic haemolytic anaemia



PK converts phosphoenolpyruvate to pyruvate, creating 50% of red cell's ATP

Red cell longevity is reliant on ATP availability --> shortened life span

Younger cells are more dependent on ATP & so more affected by deficiency

Travel through the splenic capillaries damages affected cells --> removal from circulation by liver and spleen


Autosomal recessive

50 cases per 1 million of general population. Increased in Amish and Romani groups

Over 200 known causative mutations


clinical features

Highly variable between individuals

  • Prenatal hydrops fetalis

  • Neonatal hyperbilirubinaemia --> phototherapy and exchange transfusion

  • Children can be transfusion-dependent for years, even after splenectomy

  • Stabilises in adulthood



Blood film - may be normal or typical of PK (prominent echinocytes, increased after splenectomy)

PK Enzyme activity test

PK-LR gene testing



Folic acid

Splenectomy (consider cholecystectomy at time of surgery)

Iron overload management

Pregnancy - increased haemolysis so care required but successful pregnancies are possible

Manage extramedullary haematopoeisis (leg ulcers, spinal cord compression)