The prevalence of isolated unconjugated hyperbilirubinaemia (Gilbert's syndrome) in subjects attending a health screening programme in Singapore.

We retrospectively studied the prevalence of hyperbilirubinaemia in 1,296 consecutive subjects attending a hospital health screening programme over an eighteen-month period. Sixty-four subjects (5%) had elevated bilirubin levels. Forty-one subjects (3.2%) had isolated unconjugated hyperbilirubinaemia. These subjects probably had Gilbert's syndrome. Recognition of this common benign condition is important to avoid unnecessary investigations.