This post explains what are the causes of gallstones, their risk factors, and the symptoms you should look out for.
It is not yet clear what causes the formation of gallstones, but they are thought to be caused due to an imbalance in the chemical composition of bile inside the gallbladder. Why this imbalance occurs is not clear.
Gallstones typically form between the age of 20 to 40 years but show symptoms much later. They are mostly seen in adults but rarely some children may develop them.
Causes of gallbladder formation
Gallstones can develop when:
- When the cholesterol excreted by the liver gets highly concentrated in the bile. This happens when the chemicals in bile do not completely dissolve the cholesterol because the liver excretes too much of it, which the bile cannot dissolve. This excess cholesterol then forms crystals that over the years grow and form cholesterol gallstones. According to NIH, high blood levels of serum cholesterol, high serum LDL, and low levels of serum HDL may increase the excretion of cholesterol from the liver in the bile and cause cholesterol gallstone disease.
- When the bile is highly concentrated with bilirubin. Bilirubin is a yellowish substance, that the body makes during the breakdown of red blood cells. The liver takes up the bilirubin from the blood and excretes it into bile to be further excreted from the intestines through the feces. Certain conditions of the liver such as liver cirrhosis, biliary tract infections, and certain blood disorders like hemolytic anemia in which red blood cells are destroyed faster than they’re made, cause the liver to make and excrete too much bilirubin. The excess bilirubin in bile leads to pigment gallstone formation.
- There is abnormal gallbladder function. For some reason, when the gallbladder does not work and empty completely, the bile stays stagnant in it, thickens, and forms sludge. This is called microlithiasis. Biliary sludge is a viscous gel made of mucin, cholesterol precipitates, and calcium bilirubinate. Gallstone formation is usually preceded by the presence of biliary sludge. The sludge can thicken further and the compounds of cholesterol and bilirubin present in bile can form crystals, which over time can lead to gallstone formation.
Factors that can increase your risk of gallstone formation include:
If you have a family history of gallstones, your chances of developing them are high. Genes contribute about 25% of your overall risk for developing gallstones.
Gallstone disease is rare before the age of 20. The risk increases as you age and is maximum after the age of 40 years.
Certain drugs when taken long-term are held responsible for gallstone disease. The most common ones include ceftriaxone, clofibrate, oral contraceptives, estrogen replacement, progestogens, and octreotide.
Some drugs are present in bile and they may precipitate and form stones. Other drugs can produce gallbladder stasis with associated increases in cholesterol concentration in the bile.
The prevalence of gallstones is higher in women than in men. Studies have shown that gallstones are common in young women but rare in young men. However, with increasing age, the difference narrows down.
The increased risk in women is due to hormonal reasons. Estrogen promotes cholesterol saturation of the bile while progesterone may inhibit contraction of the gallbladder.
Geography and Ethnicity
A high prevalence of gallstone disease is seen in
- The Pima Indians of Arizona
- The original Micmac Indians of Canada,
- Non-Hispanic whites
- Mexican American women
- Men and women in Norway and Chile
- Blacks show a lowered risk
Central obesity is a significant risk factor for gallstone disease. Obese women are more prone than obese men are. Obesity in women doubles the risk as compared to normal-weight women.
Increased vigorous physical activity appears to reduce gallstone disease risk.
Rapid weight loss
Individuals who lose weight rapidly or those who have undergone surgical weight-loss procedures are at significant risk of gallstone formation.
In such a scenario, cholesterol from the adipose tissue is released and secreted into the bile, which leads to supersaturation of bile with cholesterol and diminished gallbladder contraction.
Other risk factors include:
- Cholesterol-lowering drugs
- Crohn’s disease in the terminal ileum
- High estrogen levels from pregnancy or birth control pills
- Liver disease
- Bile duct infection
Symptoms of a gallbladder attack
Most people with gallstones do not show any symptoms. Such gallstones that do not cause symptoms are called silent gallstones. They do not cause any functional problems and therefore, they do not require treatment.
Nearly two-thirds of patients with gallstones do not show symptoms. Studies suggest that the increased likelihood of developing gallstone pain after 10 years varies from 15% to 25%.
The signs and symptoms of gallstones are present when the gallstone lodges in one of the biliary ducts, gets stuck, and causes a blockage of the duct. The stone could completely block the ducts of the gallbladder, liver, common bile duct, or pancreas. Due to blockage, bile could build up in your gallbladder, causing a gallbladder attack pain. This is called biliary colic.
Interestingly, it is the small stones that can often cause the most trouble. Being small they can leave the gallbladder and get stuck in the duct. Larger stones tend to remain silently in the gallbladder.
The typical symptoms of gallbladder pain may last several minutes to a few hours and can be so intense that you can’t sit still. Gallbladder attacks often come after a heavy meal usually in the evening or during the night.
Characteristics of gallbladder pain:
- Rapidly increasing pain of sudden onset in the upper right portion of your abdomen or in the center of your abdomen below your breastbone
- Back pain between your shoulder blades
- Pain in your right shoulder
Other symptoms include:
- Nausea or vomiting
- Indigestion, heartburn, and gas
- Yellowing of skin and the whites of the eyes (jaundice)
- High fever with chills
- Dark-colored urine and light-colored feces
The symptoms of gallstones stop when the stone moves and no longer block the bile ducts.
You should seek medical care if the following emergency symptoms of gallbladder attack last more than two hours.
- Severe abdominal pain in the upper right area of the abdomen that can spread to the shoulder or upper back
- You have vomiting and nausea
- You develop fever, which is the sign of infection