Atypical intraerythrocytic pyruvate kinase in some haematological diseases.

An atypical pyruvate kinase (PK) in erythrocytes was studied in a family with several different haematological diseases: non-spherocytic haemolysis, thrombocytopenia, myelofibrosis and polycythaemic traits. Atypical intraerythrocytic PK was also found in a group of non-related patients with myelofibrosis and polycythaemia vera. The atypical PK was characterised by abnormal urea inhibition and other relevant biochemical parameters.