03 Pediatric

Gilbert syndrome is a hereditary, chronic or recurrent, mild unconjugated hyperbilirubinemia with otherwise normal liver function tests.

This syndrome is the result of a defective promoter UGT1A1 gene encoding for the bilirubin uridine diphosphoglucoronate-glucuronosyltransferase (bilirubin-UGT)

The result is the inability to conjugate bilirubin with glucuronic acid.

The syndrome is relatively common, affecting between 4-16% people.

Gilbert syndrome is more commonly diagnosed in males.

Most patients with Gilbert syndrome are asymptomatic.

When symptomatic, patients with Gilbert syndrome present with episodes of intermittent mild jaundice.

Often patients are first identified by an elevated serum bilirubin on routine blood chemistry or mild jaundice (perhaps only scleral icterus) during a period of fasting associated with viral illness or rigorous activities.

Generally, a diagnosis of Gilbert syndrome can be made when there is a mild, fluctuating unconjugated hyperbilirubinemia, otherwise normal liver function tests and no hemolysis.

Gilbert syndrome is generally believed to have no significant negative health implications and treatment is generally not required.

Patients with Gilbert syndrome may be more susceptible to toxicity of drugs that require metabolism through glucuronidation, such as:

• Irinotecan

• Acetaminophen

• Tolbutamide