From the Guidelines
Gilbert syndrome is a benign, inherited condition that does not require specific treatment, and individuals with this condition can lead normal lives without complications, as long as they maintain good hydration and regular eating patterns to minimize episodes of jaundice. This condition is characterized by elevated levels of unconjugated bilirubin in the blood, causing occasional mild jaundice, and it affects about 3-7% of the population 1. People with Gilbert syndrome have a genetic mutation that reduces the activity of an enzyme called UGT1A1, which is responsible for processing bilirubin, and symptoms, when they occur, are usually triggered by stress, fasting, dehydration, illness, or intense exercise. Some key points to consider in the management of Gilbert syndrome include:
- Maintaining good hydration and regular eating patterns to minimize episodes of jaundice
- Informing healthcare providers about the condition to avoid unnecessary testing when mild jaundice appears
- No special medical follow-up is required for this benign condition
- In clinical trials, it is essential to accurately identify Gilbert's Syndrome to avoid misdiagnosis and unnecessary diagnostic testing, and to use direct bilirubin levels for decision making, with a reasonable threshold of direct bilirubin >2 x baseline to trigger action 1. Overall, Gilbert syndrome is a mild liver disorder that does not cause liver damage or affect liver function, and with proper management, individuals with this condition can lead normal lives without complications.
From the Research
Definition and Characteristics of Gilbert Syndrome
- Gilbert syndrome is a benign condition characterized by asymptomatic sporadic episodes of jaundice, due to a mild unconjugated hyperbilirubinemia caused by a deficiency in bilirubin glucoronidation 2.
- It is a common autosomal dominant hereditary condition with incomplete penetrance and characterized by intermittent unconjugated hyperbilirubinemia in the absence of hepatocellular disease or hemolysis 3.
- In patients with Gilbert syndrome, uridine diphosphate-glucuronyl transferase activity is reduced to 30% of the normal, resulting in indirect hyperbilirubinemia 3.
Diagnosis and Diagnostic Criteria
- The clinical diagnosis of Gilbert's syndrome can be established with relative certainty if the patients have a mild hyperbilirubinemia with a high fraction of unconjugated bilirubin, normal values of liver enzymes, and no overt signs of hemolysis 4.
- Molecular genetic tests can now be performed when there is a diagnostic problem, and the most common genotype of Gilbert syndrome is the homozygous polymorphism A(TA)7TAA in the promoter of the gene for UDP-glucuronosyltransferase 1A1 (UGT1A1) 3.
- Assessment of bilirubin concentrations is typically conducted as part of routine liver function testing, and mildly elevated total bilirubin with normal serum activities of liver transaminases, biliary damage markers, and red blood cell counts may indicate the presence of Gilbert's syndrome 5.
Treatment and Management
- No specific management is necessary as Gilbert syndrome is a benign condition 3.
- Phenobarbital treatment has been shown to improve the clearance of unconjugated bilirubin from plasma and increase serum GGT activity and urinary d-glucaric acid excretion 6.
Complications and Associated Conditions
- Gilbert syndrome in combination with other prevailing conditions such as breast feeding, G-6-PD deficiency, thalassemia, spherocytosis, or cystic fibrosis may potentiate severe hyperbilirubinemia and/or cholelithiasis 3.
- Mildly elevated unconjugated bilirubin in GS is strongly associated with "reduced" prevalence of chronic diseases, particularly cardiovascular diseases (CVD) and type 2 diabetes mellitus (and associated risk factors), as well as CVD-related and all-cause mortality 5.