This inherited disorder occurs when the bilirubin is not metabolized by the liver and as the result, it causes jaundice. Bilirubin is the material that is produced when the red blood cells in the body are broken down. The liver then processes the toxic bilirubin into conjugated bilirubin after a certain chemical reaction. It is estimated that around 30% of the individuals with this disorder do not present any symptoms associated with this condition. As the bilirubin levels tend to fluctuate, rarely the level increases to cause jaundice among the affected individuals. Gilbert syndrome is a common condition that appears to affect around 3 to 7 % of the Americans.
Causes
Gilbert disease occurs as the result of a mutation in the gene identified as UGT1A1 which is essential for the production of an enzyme known as bilirubin-UGT. The genetic mutation affects the normal production of the enzyme and as the result; this toxic substance accumulates in the body causing the symptoms associated with this disease. It is estimated that the affected cases tend to have 30% of the normal function of the bilirubin-UGT enzyme. The inheritance pattern varies and can develop as the result of the autosomal recessive pattern when both the copies of the gene in each cell are defective or can occur as an autosomal dominant pattern when one altered gene is sufficient to cause this disease.
Symptoms
Although this disease may be apparent after the birth of the infant, it may not be evident for several years. The only sign of gilbert disease is the indication of the yellowish color of the skin (jaundice) and the whites of the eyes resulting from the bilirubin accumulation in the blood. In addition, others have reported unspecific symptoms such as abdominal discomfort, nausea and diarrhea. Some of the factors that can increase the bilirubin levels in their body include dehydration, lack of sleep, stress, menstruation, fasting, other illness and strenuous exercise.
Diagnosis
This disease is often diagnosed when blood analysis required for another condition detects the mildly increased bilirubin levels. In such cases, the individual will be asked about the presence of additional symptoms such as abdominal pain or the dark colored urine. Additional tests may also be required to rule out other possible causes that can contribute to the increase in bilirubin level. This can include liver function tests and complete blood count. Genetic testing that identifies the gene responsible for causing this disease can also confirm the diagnosis.
Treatment
In most of the cases, the treatment for gilbert disease is not required as it does not always cause symptoms. This is a usually a harmless condition and when the bilirubin level increases in the blood, the affected individual may experience jaundice which can resolve on its own.
References
http://www.mayoclinic.org/diseases-conditions/gilberts-syndrome/basics/treatment/con-20024904
https://rarediseases.org/rare-diseases/gilbert-syndrome/
https://ghr.nlm.nih.gov/condition/gilbert-syndrome#inheritance