Gilbert's Syndrome

Gilbert's syndrome is also often referred to as Gilbert's disease but this is not accurate as this disorder possibly brings more positives than negatives. Gilbert's syndrome is usually diagnosed by young males but it may affect women as well.


The disorder is caused by an inherited genetically caused enzymatic defect in liver. People with Gilbert's syndrome have defective enzyme known as glucuronyl transferase. This is an important detoxification enzyme responsible for so-called conjugation of many substances that the body needs to eliminate. Conjugation increases the solubility in water, thus improving the elimination process. One of these substances is called bilirubin.


Bilirubin has a tight relationship with red blood cells (erythrocytes). These cells carry oxygen thanks to a blood pigment known as hemoglobin. Hemoglobin molecules bind the oxygen and allow its transport. When a red blood cell is disintegrated, the hemoglobin is splat up into hem and globin. Hem is further decomposed and bilirubin is the final product of its metabolism. Such newly formed bilirubin is unconjugated, thus insoluble in water. It is brought into the liver where it is conjugated in liver cells and excreted into bile. When there is a biliary tract obstruction, conjugated bilirubin may be excreted even by urine.


Patients with Gilbert's syndrome have decreased activity of the glucuronyl transferase and in some occasions (fatigue, infections, increased breakdown of red blood cells, alcohol excess, chemotherapy administration, surgical interventions etc.) the bilirubin conjugation may become insufficient causing accumulation of unconjugated bilirubin in the body.


The symptoms usually occur in bouts related to the above-mentioned strenuous situations. Accumulated bilirubin may cause mild jaundice and various other symptoms such as fatigue, nausea, loss of appetite and abdominal pain. Between such bouts, the person is completely healthy and without any problems. However, not all cases of jaundice in a young person is Gilbert's syndrome and more serious pathologies should be excluded (infectious hepatitis, hemochromatosis, Wilson's disease, etc.).


Young patient with a suddenly occurred jaundice and other above-mentioned troubles shall be cautiously examined. Physical examination should be focused on abdomen, especially to rule out liver enlargement. Blood tests can help us to evaluate liver tests and bilirubin serum level. In addition to total bilirubin level we should also know unconjugated and conjugated bilirubin levels as unconjugated bilirubin should be distinctively elevated in this case. Serologic exclusion of infectious hepatitis is highly advisable. From imaging methods, at least abdominal ultrasound focused on liver and biliary tree should be done. We should not find any other important pathology except of elevated unconjugated and total bilirubin in a classic case of Gilbert's syndrome.


Gilbert's syndrome is inherited and therefore can not be cured. In addition, it has been found out that the unconjugated bilirubin brings many positives* to its carrier. Accumulated unconjugated bilirubin serves as an excellent scavenger of free oxygen radicals and thus helps to fight the so-called oxidative stress and reduces risks of atherosclerosis and malignant diseases. Patients suffering from Gilbert's syndrome should try to reduce the frequency of bouts by avoiding heavy physical exercise and by only reasonable alcohol drinking.


However, Gilbert's syndrome does not have only positives. It is important to realize that a person with Gilbert's syndrome has defective an important enzyme improving the elimination of many harmful substances. Therefore, any patient with diagnosed Gilbert’s syndrome should inform the doctors about his condition before any anesthesia or chemotherapy.


* This is not true in newborns as unconjugated bilirubin can pass through hematoencephalic barrier into the brain and damage it. Brains of adults are insensitive to bilirubin effect.


Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Sources: basic text sources