Pyruvate kinase deficiency associated with severe liver dysfunction in the newborn.

Significant hyperbilirubinaemia, anemia, and splenomegaly are common features in patients with severe haemolysis due to pyruvate kinase (PK) deficiency. Until now, severe neonatal PK deficiency has not been associated with fatal liver disease at this age. We present two neonatal cases of severe PK deficiency complicated with progressive fatal liver disease. The patients presented with severe haemolysis, progressive cholestasis, and hepatosplenomegaly, and both patients ultimately developed liver failure at a very young age. Despite extensive investigations, no specific explanation for liver disease and failure was found. We suggest that the PK deficiency itself directly led to liver dysfunction.