gallstone

gallstone: see gall bladder.

Mass of crystallized substances that forms in the gallbladder. The most common type occurs when the liver secretes bile with too much cholesterol to stay in solution. Liver damage, chronic gallbladder disease, or biliary-tract cancer may predispose one to stone formation. In the gallbladder, stones may cause inflammation or produce no symptoms. A stone obstructing the bile duct causes severe pain (biliary colic). Gallstones usually must be removed with the gallbladder or broken up with ultrasound. In some cases a stone can be treated by giving the patient bile salts, which help redissolve cholesterol. If the gallbladder must be removed, laparoscopy is the method of choice.

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In medicine, gallstones (choleliths) are crystalline bodies formed within the body by accretion or concretion of normal or abnormal bile component.

Gallstones can occur anywhere within the biliary tree, including the gallbladder and the common bile duct. Obstruction of the common bile duct is choledocholithiasis; obstruction of the biliary tree can cause jaundice; obstruction of the outlet of the pancreatic exocrine system can cause pancreatitis. Cholelithiasis is the presence of stones in the gallbladder—chole- means "bile", lithia means "stone", and -sis means "process".

The characteristics of gallstones are various. Independent of appearance, however, gallstones are valuable on the market.

Characteristics

Size

A gallstone's size varies and may be as small as a sand grain or as large as a golf ball. The gallbladder may develop a single, often large stone or many smaller ones. They may occur in any part of the biliary system.

Content

Gallstones have different appearance, depending on their contents. On the basis of their contents, gallstones can be subdivided into the two following types:

• Cholesterol stones are usually green, but are sometimes white or yellow in color. They are made primarily of cholesterol.
• Pigment stones are small, dark stones made of bilirubin and calcium salts that are found in bile. They account for 20 percent of gallstones. Risk factors for pigment stones include hemolytic anemia, cirrhosis, biliary tract infections, and hereditary blood cell disorders, such as sickle cell anemia and spherocytosis.

Mixed stones

Mixed stones account for the majority of stones. Most of these are a mixture of cholesterol and calcium salts. Because of their calcium content, they can often be visualized radiographically.

Pseudolithiasis

A.k.a., "Fake stone" Sludge-like gallbladder secretions that act like a stone.

Causes

Researchers believe that gallstones may be caused by a combination of factors, including inherited body chemistry, body weight, gallbladder motility (movement), and perhaps diet. Additionally, people with erythropoietic protoporphyria (EPP) are at increased risk to develop gallstones.

Cholesterol gallstones develop when bile contains too much cholesterol and not enough bile salts. Besides a high concentration of cholesterol, two other factors seem to be important in causing gallstones. The first is how often and how well the gallbladder contracts; incomplete and infrequent emptying of the gallbladder may cause the bile to become overconcentrated and contribute to gallstone formation. The second factor is the presence of proteins in the liver and bile that either promote or inhibit cholesterol crystallization into gallstones.

In addition, increased levels of the hormone estrogen as a result of pregnancy, hormone therapy, or the use of combined (estrogen-containing) forms of hormonal contraception, may increase cholesterol levels in bile and also decrease gallbladder movement, resulting in gallstone formation.

No clear relationship has been proven between diet and gallstone formation. However, low-fibre, high-cholesterol diets, and diets high in starchy foods have been suggested as contributing to gallstone formation. Other nutritional factors that may increase risk of gallstones include rapid weight loss, constipation, eating fewer meals per day, eating less fish, and low intakes of the nutrients folate, magnesium, calcium, and vitamin C. On the other hand, wine and whole grain bread may decrease the risk of gallstones.

The common mnemonic for gallstone risk factors refer to the "four F's": fat (i.e., overweight), forty (an age near or above 40), female, and fertile (pre-menopausal); a fifth F, fair is sometimes added to indicate that the condition is more prevalent in Caucasians. The absence of these risk factors does not, however, preclude the formation of gallstones.

Symptoms

Gallstones usually remain asymptomatic initially. They start developing symptoms once the stones reach a certain size (>8mm). A main symptom of gallstones is commonly referred to as a gallstone "attack", also known as biliary colic, in which a person will experience intense pain in the upper abdominal region that steadily increases for approximately thirty minutes to several hours. A patient may also encounter pain in the back, ordinarily between the shoulder blades, or pain under the right shoulder. In some cases, the pain develops in the lower region of the abdomen, nearer to the pelvis, but this is less common. Nausea and vomiting may occur.

These attacks are sharp and intensely painful, similar to that of a kidney stone attack. One way to alleviate the abdominal pain is to drink a full glass of water at the start of an attack to regulate the bile in the gallbladder, but this does not work in all cases. Another way is to take magnesium followed by a bitter liquid such as coffee or swedish bitters an hour later. Bitter flavors stimulate bile flow. A study has found lower rates of gallstones in coffee drinkers.

Often, these attacks occur after a particularly fatty meal and almost always happen at night. Other symptoms include abdominal bloating, intolerance of fatty foods, belching, gas, and indigestion. If the above symptoms coincide with chills, lowgrade fever, yellowing of the skin or eyes, and/or clay-colored stool, a doctor should be consulted immediately.

Some people who have gallstones are asymptomatic and do not feel any pain or discomfort. These gallstones are called "silent stones" and do not affect the gallbladder or other internal organs. They do not need treatment.

Treatment

Medical options

Cholesterol gallstones can sometimes be dissolved by oral ursodeoxycholic acid, but it may be required that the patient takes this medication for up to two years. Gallstones may recur however, once the drug is stopped. Obstruction of the common bile duct with gallstones can sometimes be relieved by endoscopic retrograde sphincterotomy (ERS) following endoscopic retrograde cholangiopancreatography (ERCP). Gallstones can be broken up using a procedure called lithotripsy (Extracorporeal Shock Wave Lithotripsy), which is a method of concentrating ultrasonic shock waves onto the stones to break them into tiny pieces. They are then passed safely in the feces. However, this form of treatment is only suitable when there are a small number of gallstones.

Surgical options

Cholecystectomy (gallbladder removal) has a 99% chance of eliminating the recurrence of cholelithiasis. Only symptomatic patients must be indicated to surgery. The lack of a gall bladder does not seem to have any negative consequences in many people. However, there is a significant proportion of the population, between 5-40%, who develop a condition called postcholecystectomy syndrome.Symptoms include gastrointestinal distress and persistent pain in the upper right abdomen. As many as twenty percent of patients develop chronic diarrhea.

There are two surgery options: open procedure and laparoscopic: see the cholecystectomy article for more details.

• Open cholecystectomy procedure: This involves a large incision into the abdomen (laparotomy) below the right lower ribs. A week of hospitalization, normal diet a week after release and normal activity a month after release.
• Laparoscopic cholecystectomy: Three to four small puncture holes for camera and instruments (available since the 1980s). Typically same-day release or one night hospital stay, followed by a week of home rest and pain medication. Can resume normal diet and light activity a week after release. (Decreased energy level and minor residual pain for a month or two.) Studies have shown that this procedure is as effective as the more invasive open cholecystectomy, provided the stones are accurately located by cholangiogram prior to the procedure so that they can all be removed. The procedure also has the benefit of reducing operative complications such as bowel perforation and vascular injury.

Alternative medicine

A regimen called a "gallbladder flush" or "liver flush" is a popular remedy in alternative medicine. In this treatment, often self-administered, the patient drinks four glasses of pure apple juice (not cider) and eats five apples (or applesauce) per day for five days, then fasts briefly, takes magnesium, and then drinks large quantities of lemon juice mixed with olive oil before bed. The next morning, they painlessly pass a number of green and brown pebbles purported to be stones flushed from the biliary system.

A New Zealand hospital analyzed stones from a typical gallbladder flush and found them to be composed of fatty acids similar to those in olive oil, with no detectable cholesterol or bile salts, demonstrating that they are little more than hardened olive oil. Despite the gallbladder flush, the patient still required surgical removal of multiple true gallstones. The note concluded: "The gallbladder flush may not be entirely worthless, however; there is one case report in which treatment with olive oil and lemon juice resulted in the passage of numerous gallstones, as demonstrated by ultrasound examination."

In the case mentioned, ultrasound confirmed multiple gallstones, but after waiting months for a surgical option, the patient underwent a treatment with olive oil and lemon juice resulting in the passage of four 2.5–cm by 1.25–cm stones and twenty pea-sized stones. Two years later symptoms returned, and ultrasound showed a single large gallstone; the patient chose to have this removed surgically.

Other patients have noticed that symptoms can be reduced by drinking several glasses of water when experiencing gallstone pain. This will obviously not eliminate the gallstones, but can temporarily reduce the pain.

Value

Gallstones are a valuable by-product of meat processing, fetching up to US$32–per–gram in their use as a purported antipyretic and antidote in the herbal medicine of some cultures, particularly in China. The finest gallstones tend to be sourced from old dairy cows, which are called Niu-Huang (yellow thing of oxen) in Chinese. Those obtained from dogs, called Gou-Bao (treasure of dogs) in Chinese, are also used today. Much as in the manner of diamond mines, slaughterhouses carefully scrutinize offal department workers for gallstone theft.

References

External links

• Public domain NIH/NIDDK e-pub on gallstones