Caeruloplasmin isoforms in Wilson's disease in neonates.

AIM To investigate the neonatal diagnosis of Wilson's disease from caeruloplasmin isoforms in cord blood. METHODS Serum caeruloplasmin isoforms were measured in 5-10 ml cord blood from 10 fresh umbilical cords using sodium dodecyl polyacrylamide gel electrophoresis (SDS PAGE) and western blotting and analysed by densitometry. Total caeruloplasmin concentrations were determined by nephelometry and caeruloplasmin oxidase by p-nitrophenyldiamine. RESULTS Although total caeruloplasmin concentrations are reduced in neonates, the plasma isoform was significantly reduced or absent in patients with Wilson's disease. Sera from healthy neonates and from those with Wilson's disease had reduced biliary isoforms. CONCLUSION Identification of caeruloplasmin isoforms may be a marker for Wilson's disease in neonates.