Cholelithiasis is the medical name for hard deposits (gallstones) that may form in the gallbladder. Cholelithiasis is common in the United States population. Six percent of adult men and 10% of adult women are affected.
The cause of cholelithiasis is not completely understood, but it is thought to have multiple factors. The gallbladder stores bile and releases it into the small intestine when it is needed for digestion. Gallstones can develop if the bile contains too much cholesterol or too much bilirubin (one of the components of bile), or if the gallbladder is dysfunctional and cannot release the bile.
Different types of gallstones form in cholelithiasis. The most common type, called a cholesterol stone, results from the presence of too much cholesterol in the bile. Another type of stone, called a pigment stone, is formed from excess bilirubin, a waste product created by the breakdown of the red blood cells in the liver. The size and number of gallstones varies in cholelithiasis; the gallbladder can form many small stones or one large stone.
The course of cholelithiasis varies among individuals. Most people with cholelithiasis have no symptoms at all. A minority of patients with gallstones develop symptoms: severe abdominal pain, nausea and vomiting, and complete blockage of the bile ducts that may pose the risk of infection.
Cholelithiasis can lead to cholecystitis, inflammation of the gallbladder. Acute gallstone attacks may be managed with intravenous medications. Chronic (long-standing) cholelithiasis is treated by surgical removal of the gallbladder.
Signs and symptoms of Cholelithiasis
Gallstone disease may be thought of as having the following 4 stages:
♦ Lithogenic state, in which conditions favor gallstone formation
♦ Asymptomatic gallstones
♦ Symptomatic gallstones, characterized by episodes of biliary colic
♦ Complicated cholelithiasis
Symptoms and complications result from effects occurring within the gallbladder or from stones that escape the gallbladder to lodge in the CBD.
Characteristics of biliary colic include the following:
♦ Sporadic and unpredictable episodes
♦ Pain that is localized to the epigastrium or right upper quadrant, sometimes radiating to the right scapular tip
♦ Pain that begins postprandially, is often described as intense and dull, typically lasts 1-5 hours, increases steadily over 10-20 minutes, and then gradually wanes
♦ Pain that is constant; not relieved by emesis, antacids, defecation, flatus, or positional changes; and sometimes accompanied by diaphoresis, nausea, and vomiting
♦ Nonspecific symptoms (eg, indigestion, dyspepsia, belching, or bloating)
Patients with the lithogenic state or asymptomatic gallstones have no abnormal findings on physical examination.
Distinguishing uncomplicated biliary colic from acute cholecystitis or other complications is important. Key findings that may be noted include the following:
♦ Uncomplicated biliary colic – Pain that is poorly localized and visceral; an essentially benign abdominal examination without rebound or guarding; absence of fever
♦ Acute cholecystitis – Well-localized pain in the right upper quadrant, usually with rebound and guarding; positive Murphy sign (nonspecific); frequent presence of fever; absence of peritoneal signs; frequent presence of tachycardia and diaphoresis; in severe cases, absent or hypoactive bowel sounds
The presence of fever, persistent tachycardia, hypotension, or jaundice necessitates a search for complications, which may include the following:
♦ Other systemic causes
♦ For symptomatic stones: Laparoscopic cholecystectomy or sometimes stone dissolution using ursodeoxycholic acid
♦ For asymptomatic stones: Expectant management
Most asymptomatic patients decide that the discomfort, expense, and risk of elective surgery are not worth removing an organ that may never cause clinical illness. However, if symptoms occur, gallbladder removal (cholecystectomy) is indicated because pain is likely to recur and serious complications can develop.
Surgery: Surgery can be done with an open or a laparoscopic technique.
Open cholecystectomy, which involves a large abdominal incision and direct exploration, is safe and effective. Its overall mortality rate is about 0.1% when done electively during a period free of complications.
Laparoscopic cholecystectomy is the treatment of choice. Using video endoscopy and instrumentation through small abdominal incisions, the procedure is less invasive than open cholecystectomy. The result is a much shorter convalescence, decreased postoperative discomfort, improved cosmetic results, yet no increase in morbidity or mortality. Laparoscopic cholecystectomy is converted to an open procedure in 2 to 5% of patients, usually because biliary anatomy cannot be identified or a complication cannot be managed. Older age typically increases the risks of any type of surgery.
Cholecystectomy effectively prevents future biliary colic but is less effective for preventing atypical symptoms such as dyspepsia. Cholecystectomy does not result in nutritional problems or a need for dietary limitations. Some patients develop diarrhea, often because bile salt malabsorption in the ileum is unmasked. Prophylactic cholecystectomy is warranted in asymptomatic patients with cholelithiasis only if they have large gallstones (> 3 cm) or a calcified gallbladder (porcelain gallbladder); these conditions increase the risk of gallbladder carcinoma.
Stone dissolution: For patients who decline surgery or who are at high surgical risk (eg, because of concomitant medical disorders or advanced age), gallbladder stones can sometimes be dissolved by ingesting bile acids orally for many months. The best candidates for this treatment are those with small, radiolucent stones (more likely to be composed of cholesterol) in a functioning nonobstructed gallbladder (indicated by normal filling detected during cholescintigraphy or oral cholecystography or by absence of stones in the neck).
Ursodeoxycholic acid 4 to 5 mg/kg po bid or 3 mg/kg po tid (8 to 10 mg/kg/day) dissolves 80% of tiny stones < 0.5 cm in diameter within 6 mo. For larger stones (the majority), the success rate is much lower, even with higher doses of ursodeoxycholic acid. Further, after successful dissolution, stones recur in 50% within 5 yr. Most patients are thus not candidates and prefer laparoscopic cholecystectomy. However, ursodeoxycholic acid 300 mg po bid can help prevent stone formation in morbidly obese patients who are losing weight rapidly after bariatric surgery or while on a very low calorie diet.