Gallstones (Cholelithiasis)

Excerpt

Gallstones are among the most common causes of gastrointestinal dysfunction in the United States and worldwide. Gallstones can cause both chronic pain and episodic discomfort. They also cause acute disorders affecting the pancreatic, biliary, hepatic, and gastrointestinal tract. In the United States, over 6.3 million men and 14.2 million women between the ages of 20 and 74 have gallstones. Although most individuals with gallstones are asymptomatic, about 10% may develop symptoms within 5 years and 20% within 20 years of diagnosis. The prevalence of gallstones increases with age. Over 25% of women older than 60 have gallstones. See Image. Gallstones.

Gallstones arise from metabolic, environmental, and genetic factors, and their composition depends on the etiology. Gallstones can manifest as sand-like debris or form larger stones that can grow to several centimeters in diameter. Typically mobile within the gallbladder, they can also become fixed, either within the body of the gallbladder or at the opening of the cystic duct, disrupting the episodic gallbladder contractility, impairing perfusion, and promoting infection. When gallstones impede gallbladder function and block bile flow, biliary colic results as the gallbladder contracts against partially obstructing stones.

Biliary colic occurs as intermittent, post-prandial epigastric or right upper quadrant pain, and can also be associated with incomplete obstruction within the cystic or common bile duct. Colic may initially be self-limiting and does not typically require hospital admission, but can progress and become unrelenting, leading to inflammation and constant discomfort. Prolonged obstruction or complete impaction of a stone within the biliary tree can result in cholecystitis or cholangitis; at this point, the pain will be constant and progressive. If the cystic duct is obstructed for more than a few hours, the gallbladder becomes inflamed and is prone to infiltration of gut bacteria. Biliary obstruction leads to severe abdominal pain, cholangitis, and pancreatitis. Persons with chronic gallstones may develop progressive fibrosis and loss of gallbladder motility.

Ultrasound is the preferred diagnostic modality for detecting gallstones, but gallstones may be visualized on computed tomography (CT), magnetic resonance imaging (MRI), and, depending on calcium content, even on x-rays. See Image. Gallstone, Ultrasound Image. Treatment for gallstones depends on the clinical acuity and symptoms. See Image. Acute Cholecystitis Wall Thickening With Pericholecystic Fluid Gallstone, Computed Tomography. The standard of care for patients experiencing recurrent biliary colic or acute cholecystitis is laparoscopic cholecystectomy. One million cholecystectomies are performed annually in the United States, at least half of which are secondary to biliary colic and chronic cholecystitis.