Epidemiology of unconjugated hyperbilirubinemia: revisited

It is currently believed that unconjugated hyperbilirubinemia occurs in about 5% of western populations, although only a modest proportion of these persons present clinically. There is increasing awareness that the definition of the normal serum bilirubin level is complex, as demonstrated by recent population studies, which will be reviewed in the first part of this article. The second part will address the diagnostic problems that arise once hyperbilirubinemia has been recognized. Finally, some aspects of the mode of inheritance of familial hyperbilirubinemia will be discussed.