Increased activity of 5' nucleotidase in serum of patients with sickle cell anaemia.

Fifty-nine patients with homozygous sickle cell anaemia, 17 heterozygous individuals and 22 controls were investigated in respect to serum (S) 5'nucleotidase (5'NT, EC 3.1.3.5). The patients showed a significantly higher mean value of S-5'NT compared to the controls. However, this rise was heterogeneous as it occurred only among a subgroup of patients. The heterozygous individuals were not different from either the patients or the controls generating a situation which puts the heterozygous individuals in an intermediate position between the patients and the controls. S-5'NT showed significant correlation with S-bilirubin, S-aspartate aminotransferase, S-alanine aminotransferase and especially S-gammaglutamyl transferase. However, it was not correlated with S-alkaline phosphatase, which is another marker for hepatobiliary disease. These results suggest that the liver involvement in a subgroup of patients with sickle cell anaemia is a mixture of hepatocyte damage and the biliary tree involvement.