GilbertSyndrom

Gilbert syndrome, also known as Gilbert disease, is a common, benign inherited condition characterized by intermittent mild unconjugated hyperbilirubinemia. It results from reduced activity of hepatic UDP-glucuronosyltransferase 1A1 (UGT1A1), the enzyme that conjugates bilirubin for elimination. The most frequent genetic cause is a promoter polymorphism in UGT1A1 (an extra TA repeat in the TATA box), and the disorder is typically inherited in an autosomal recessive pattern; individuals with two reduced-activity alleles have a higher likelihood of elevated bilirubin, while heterozygotes usually have milder or no elevations.

Most people with Gilbert syndrome have no symptoms. When jaundice occurs, it is usually mild and transient, often triggered by fasting, illness, dehydration, stress, or other factors that increase bilirubin production or reduce hepatic clearance. Bilirubin in Gilbert syndrome is predominantly unconjugated, and standard liver function tests (ALT, AST, alkaline phosphatase, and serum albumin) are typically normal. Urine and stool generally remain normal in color.

Diagnosis is usually made after excluding other causes of unconjugated hyperbilirubinemia and when there is persistently mild elevation of unconjugated bilirubin with otherwise normal liver tests. Genetic testing for UGT1A1 promoter variants can support the diagnosis, particularly when clinical and biochemical features are inconclusive.

Management is simple: provide reassurance and advise on avoiding triggers such as prolonged fasting and dehydration. No specific treatment is required for most individuals, and the prognosis is excellent, with no progression to liver disease and a normal life expectancy.