Gilbert's Syndrome

Gilbert syndrome is a hereditary, common, unconjugated hyperbilirubinaemia (high bilirubin levels in the blood). Gilbert syndrome is considered to be an autosomal recessive disorder. However, there have been cases of heterozygosity and compound heterozygosity reported in patients with Gilbert syndrome.

The characteristics of Gilbert syndrome are normal liver function tests of the usual type, liver histology, delayed clearance of bilirubin from the blood, and mild jaundice that tends to fluctuate in severity, particularly after fasting. This disorder is quite difficult to distinguish from prolonged posthepatic hyperbilirubinaemia.
Patients with Gilbert syndrome tend to have total serum bilirubin levels from 1-6 mg/dL. This is distinguished from Crigler-Najjar syndrome type II, in which patients have total serum bilirubin levels between 6 and 20 mg/dL, and Crigler-Najjar syndrome type I, in which patients have levels from 20 to 45 mg/dL.

Signs and symptoms

As an inherited condition, Gilbert's syndrome is present right from birth. Although it rarely causes symptoms, it may arise bilirubin enough to produce mild jaundice.
While the bilirubin does not reach a very dangerous level, jaundice, if it occurs, may look disconcerting. Typically, excess bilirubin turns the whites of your eyes yellow before affecting the skin. If the bilirubin level keeps rising, your skin may develop a yellowish tinge.

A number of factors may increase bilirubin if one has Gilbert's syndrome. These may include:
* Illness, including infections, such as the cold or flu
* Menstruation
* Fasting or skipping meals
* Dehydration
* Overexertion
Some people with Gilbert's experience episodes of fatigue, sometimes weakness and abdominal pain. However, it's not known if Gilbert's actually causes such symptoms, or if they're related to stress or other conditions.

Causes

The liver naturally produces bilirubin, which is a yellowish pigment. It's a normal waste product from the breakdown of old red blood cells. Bilirubin travels through bloodstream to the liver. In normal functioning, an enzyme in liver cells helps break down the bilirubin and removes it from the bloodstream. The bilirubin passes from the liver into the intestines with bile. It's then excreted by the body through stool. A small amount of bilirubin sometimes remains in the blood. People with Gilbert's syndrome, though, inherit an abnormal gene that controls the enzyme that helps break down bilirubin. This gene abnormality results in a lower level of the enzyme. Consequently, excessive amounts of a form of bilirubin called unconjugated bilirubin can then build up in the blood.
Some experts believe that Gilbert's syndrome is simply a normal variation in the range of bilirubin levels.

Screening and diagnosis

If one has jaundice, health care provider may suspect that you have Gilbert's syndrome or perhaps another condition. Often, though, Gilbert's is found purely by accident when you have blood work for other health reasons, such as an illness or to buy a life insurance policy. Although it's present from birth, Gilbert's syndrome usually is not diagnosed until puberty or later, when bilirubin production increases.

Common blood tests include:
* Complete blood count
* Liver function tests

A diagnosis of Gilbert's syndrome can usually be made from blood tests. With Gilbert's, all of the results will typically be normal except for the mildly increased level of unconjugated bilirubin.

When one has Gilbert's syndrome, the level of bilirubin in the blood may fluctuate. It's not always higher than the normal range. If initial blood test shows a normal level of bilirubin, the doctor may suggest repeating the tests a couple of times.

Doctors may suggest other tests, including:
* Ultrasound of liver
* Fasting over a 24-hour period to see if that increases bilirubin levels
* Genetic testing, which is not widely available, to check for the abnormal gene that causes Gilbert's

Treatment

Because Gilbert's syndrome is essentially a mild, harmless condition, it doesn't require treatment. The level of jaundice associated with Gilbert's is typically harmless as well, and this goes away on its own.
People with Gilbert's syndrome don't typically need long-term monitoring of their condition or repeat blood tests. But one must consult doctor if one notices worsening jaundice or other symptoms.