Causes and Risk Factors
Gallstones form when the chemical balance of bile is disturbed, allowing cholesterol or bilirubin to crystallize. Risk factors include:- Female sex and age over 40: Estrogen increases cholesterol in bile, and risk rises steadily with age.
- Excess body weight: A major risk factor for cholesterol stones.
- Rapid weight loss: Very low-calorie diets and weight-loss surgery can trigger stone formation as the liver releases extra cholesterol into bile.
- Family history: Gallstones tend to run in families.
- Metabolic conditions: Diabetes and fatty liver disease share risk factors with gallstones and often occur alongside them.
- Diet: Diets high in refined carbohydrates and low in fiber are associated with higher risk.
- Certain medications and conditions: Estrogen therapy, prolonged fasting, and diseases of the small intestine such as Crohn's disease can also promote stone formation.
Symptoms
Most gallstones are "silent" and cause no symptoms; these are usually discovered incidentally on imaging and need no treatment. A gallbladder attack (biliary colic) occurs when a stone temporarily blocks a bile duct, typically causing:- Steady upper abdominal pain: Usually in the right upper abdomen or center of the abdomen, often beginning after a rich or fatty meal or at night, lasting from thirty minutes to several hours.
- Pain radiating to the back or right shoulder blade: A classic pattern of gallbladder pain.
- Nausea and vomiting: Frequently accompany the pain.
Complications
A stone that stays lodged can cause inflammation or infection of the gallbladder (cholecystitis), blockage of the main bile duct with jaundice, infection of the bile ducts (cholangitis), or inflammation of the pancreas (pancreatitis). These conditions are serious and need urgent hospital treatment, but with prompt care most people recover fully.Diagnosis
An abdominal ultrasound is the best first test and detects most gallstones. Blood tests check for infection, liver-enzyme abnormalities, and pancreatic inflammation. When the diagnosis is unclear, a HIDA scan can assess gallbladder function, and MRCP — a specialized MRI — can look for stones in the bile ducts.Treatment
- Silent stones: Gallstones that cause no symptoms generally need no treatment, only awareness of the warning signs.
- Symptomatic stones: Once gallstones cause attacks, they tend to keep doing so. The standard treatment is laparoscopic cholecystectomy — minimally invasive removal of the gallbladder — which is one of the most common and safest operations performed, and most people digest food normally without a gallbladder.
- Nonsurgical options: For selected patients who cannot have surgery, bile-acid medication can slowly dissolve small cholesterol stones, though stones often return when it is stopped.