Gilbert’s syndrome occurs due to deficiency of the UGT enzyme that helps in conjugation of free unconjugated bilirubin.
This conjugation process by glucoronidation helps in making the bilirubin water soluble and finally helps in excretion of the bilirubin in urine and faeces.
Bilirubin is the breakdown product of dead and aged red blood cells. While the protein portion of the haemoglobin present in the red blood cells is salvaged the heme part is excreted in the bilirubin.
Gilbert’s syndrome occurs in 1 in 20 individuals. This syndrome is characterized by jaundice. However, there is a large population of sufferers who are not aware of their condition.
They have intermittent elevation of levels of bilirubin in blood that returns to normal and stays normal most of the time.
When do symptoms of Gilbert’s syndrome start to occur?
Gilbert’s syndrome is usually diagnosed between the ages of 15 and 30 years. Typically mild, asymptomatic jaundice is first noticed in teenagers.
What are the symptoms of Gilbert’s syndrome?
The symptoms of Gilbert’s syndrome include jaundice, tiredness and sometimes no symptoms at all.
Patients with Gilbert’s syndrome are prone to develop jaundice from time to time. The risk increases with other problems like starvation, dehydration, repeated and profuse vomiting, infections, exertion and stress and after a surgery. Menstruation might also be a factor in triggering off higher bilirubin levels.
Jaundice is caused by raised bilirubin in blood. The classic symptoms of jaundice include yellowish discoloration of:
Bilirubin has an orangy-yellow colour. The discoloration of skin and mucous membranes is due to the deposition of the excess bilirubin.
Eyes are the commonest affected place in patients of Gilbert’s syndrome with jaundice. There may darkening of the urine color. This is especially seen in the first morning urine.
Darkening of urine is a common feature of viral hepatitis. Many patients with Gilbert’s syndrome may not have dark urine and may have normal straw colored urine.
There is exacerbation of jaundice or precipitation of jaundice when certain drugs are taken. These include Atazanavir and indinavir (used against HIV infection), Gemfibrozil or combination of Gemfibrozil with Statins for lowering cholesterol and Irinotecan used against advanced bowel cancer.
Tiredness and weakness
Other symptoms of Gilbert’s syndrome include:
mild weakness and fatigue
mild abdominal pains especially in the upper abdomen
mild nausea and sometimes vomiting
severe loss of appetite
intolerance to fat
irritable bowel syndrome
difficulty in concentrating or focussing on tasks at hand etc.
These symptoms may be present in patients of Gilbert’s syndrome irrespective of presence or absence of frank jaundice.
Most patients present without any symptom of the condition. These patients may or may not have intermittent rise of bilirubin leading to symptoms of jaundice.
At least 30% of patients with Gilbert’s syndrome have this silent condition with no symptom whatsoever. (1-6)
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)