Gallstones

INTRODUCTION –The development of gallstones is a common digestive disease, but fortunately, most people with gallstones do not develop any symptoms or complications and do not require treatment. In many cases, such "silent gallstones" are detected incidentally through the routine use of ultrasonography for the evaluation of another problem, particularly abdominal pain or pelvic disease, or blood tests that suggest abnormal liver function. WHAT IS THE GALLBLADDER? – The gallbladder is a pear-shaped sac-like muscular organ that is approximately 3 to 6 inches long, located in the right upper side of the abdomen just underneath the liver . It connects with the liver and intestine through small tubes called the bile ducts. The primary purpose of the gallbladder is to store and concentrate bile. Bile, a greenish-brown fluid, is produced by the liver and stored in the gallbladder. Eating fatty foods causes the gallbladder to contract and empty its bile through the cystic duct, common bile duct, and the valvular opening of the sphincter of Oddi (show figure 1) into the intestine where it is needed for fatty food digestion and absorption, as well as the absorption of a number of important fat soluble vitamins. Bile is a water based fluid that contains bile salts, cholesterol, and other fatty substances (lipids), as well as waste products, such as bilirubin, a pigment that gives bile its distinctive color. During fasting, the gallbladder is relaxed and the sphincter of Oddi is closed, causing the bile that is secreted by the liver to flow through the cystic duct into the gallbladder where it is stored and concentrated by absorption of much of its water content through the gallbladder walls. This allows the gallbladder to take in and store more than 10 times its volume in bile. With meals, the entrance of fatty foods into the small intestine triggers the secretion of a hormone (cholecystokinin), which stimulates contraction of the gallbladder and the opening of the sphincter of Oddi. This results in partial emptying of the concentrated gallbladder bile through the common bile duct into the upper region of the small intestine (known as the duodenum) to aid in the digestion and absorption of fats and fat-soluble vitamins. A few hours later the gallbladder relaxes and starts to store bile secreted by the liver again. WHAT ARE GALLSTONES? – Gallstones are lumps of rock-like material that form inside the gallbladder. Medical science is just beginning to uncover the causes of gallstone formation. Studies suggest that stones can form in the gallbladder if there is a change or imbalance in the composition of bile, such as too much cholesterol, increased amounts of pigment material, and/or reduced levels of bile acids which are "detergent-like" substances that help keep the cholesterol in solution form. Evidence suggests that gallstone development may also result from an impairment of gallbladder contraction, which would lead to incomplete emptying of the gallbladder in response to a fatty meal. Due to such factors, cholesterol or other bile components may "precipitate" or settle out from liquid bile in the form of crystals that would then clump together, leading to stones. The number of gallstones can be variable. In some instances, patients may have an accumulation of minute crystals in the form of sand (called biliary sludge) but no obvious gallstone formation. Gallstones may be as small as tiny specks or as large as the gallbladder itself. The vast majority, however, are smaller than 1 inch and may be one of two major types: • Cholesterol gallstones, which account for approximately 80 percent of gallstone cases.in industrialized countries, including the United States. • Pigment stones, composed mainly of calcium salts of bile pigments and other compounds, account for about 20 percent. Gallstone type is important since cholesterol stones are more likely to respond to non-surgical treatments. WHO IS AT RISK FOR GALLSTONES? – The exact reason (or reasons) why some people develop gallstones are still being uncovered. However, there are a number of factors that may be associated with an increased risk of cholelithiasis: Gender – Women are more likely to develop gallstones than men. Age – The risk of gallstones is known to increase with age. The condition is extremely rare in childhood and becomes progressively more frequent over time, with age 40 representing a possible cut-off between relatively low and high rates. Gallstones are present in about 10 percent of men and 20 percent of women by the age of 60. Ethnicity – Gallstones appear to occur more frequently in Native American, Hispanic, and western Caucasian individuals. In contrast, there appear to be lower rates of cholelithiasis in African American, natives of South Africa, and Japanese populations. Family history and genetics – Studies of family histories indicate that cholelithiasis runs in certain families, suggesting that genetics has a role in gallstone development. Other factors – An increased risk of cholelithiasis may also be associated with a number other factors including: • Pregnancy • Use of estrogen preparations (such as birth control pills) • Obesity • Frequent fasting • Rapid weight loss • Lack of physical activity • Diabetes mellitus • Sickle cell disease (and other conditions associated with rapid destruction of red blood cells such as in patients with mechanical heart valves) • Cirrhosis, or severe scarring, of the liver • Certain medications (eg, octreotide, estrogen preparations, clofibrate) WHAT IS GALLSTONE DISEASE? – The majority of people who have gallstones do not have symptoms and their stones remain "silent." Silent stones do not need to be treated since the initial symptoms are usually mild. Experts feel that the risk from surgical removal of the gallbladder is greater than the risk from not treating silent stones. When gallstones start to produce symptoms, the condition is then referred to as gallstone disease. WHAT ARE THE SYMPTOMS OF GALLSTONES? – Once a patient experiences the first episode of symptoms, the chance of having further and more severe symptoms becomes more likely, indicating a need for treatment. Biliary colic – This is the most common symptom also referred to as gallstone pain or biliary pain. It is characterized by episodic attacks of abdominal pain, which is most often located in the right upper abdomen just under the margin of the ribs but can also be felt in the back and right shoulder. Biliary colic is usually caused by the gallbladder contracting in response to a fatty meal and pressing the stones against and blocking the gallbladder outlet (cystic duct opening). As the gallbladder relaxes several hours after the meal, the stones often fall back from the cystic duct and the pain subsides. Other associated symptoms include nausea, vomiting, and intolerance to fatty foods. Acute cholecystitis – Recurrent biliary pain and cystic duct blockages can progress to total obstruction, causing acute inflammation of the gallbladder (acute cholecystitis). Unlike biliary colic in which symptoms abate within a few hours, pain continues in patients with acute cholecystitis. This is a serious condition that is associated with fever and requires immediate medical attention. In such cases, patients require hospitalization where they are typically treated with intravenous fluids, pain medications, and often antibiotics. Surgical removal of the gallbladder is usually recommended during the hospitalization or shortly thereafter. If not treated, acute cholecystitis may lead to gallbladder rupture, a life-threatening condition. Other complications of gallstone – Other complications may result if the gallstones migrate through the cystic duct and block the common bile duct causing jaundice (a yellow discoloration of the skin and eyes) with or without pain. It may also lead to infection of the bile ducts (acute cholangitis) causing pain, chills, and fever. This condition requires prompt intervention, which usually involves a procedure in which the offending gallstone is removed by way of a tube with a video camera inserted through the mouth (a procedure known as endoscopic retrograde cholangiopancreatography or ERCP). Acute inflammation of the pancreas (pancreatitis), which is associated with severe abdominal pain, may also occur. If the bile duct remains blocked for a long period of time, irreversible liver damage may occur (secondary biliary cirrhosis). Symptoms of questionable relationship to gallstones – Gallstones are very common, as are complaints related to the digestive system such as bloating, belching, heartburn, and gas. While it is easy to mistakenly attribute these symptoms to the presence of gallstones, they usually indicate other types of gastrointestinal disorders such as gastroesophageal reflux and dyspepsia. On the other hand, episodic nausea and vomiting and intolerance to fatty foods may sometimes be suggestive of gallstone disease, although these too can be due to other causes. HOW ARE GALLSTONES DIAGNOSED? – Gallstones can be detected by a variety of methods. X-ray – An x-ray will detect only pigment stones. Ultrasound – Ultrasound is the most commonly used and most accurate screening technique since it is more sensitive than x-ray and does not involve the use of radiation. HIDA Scan – HIDA scan identifies obstructions of the cystic duct, evaluates the ability of the gallbladder to contract, and diagnoses acute cholecystitis. Endoscopic retrograde cholangiopancreatography (ERCP) – ERCP is required when gallstones are suspected in the bile ducts. A flexible tube with a video camera is inserted through the mouth and small intestine, then a smaller tube is advanced through the first tube into the bile duct through which contrast is injected and an x-ray is taken to visualize the stones. This procedure also allows the extraction of stones from the ducts without the need for surgery. CT-scan – CT scan is used to determine which gallstones are suitable for some of the non-surgical gallstone elimination modalities. However, it is a poor initial test with which to look for gallstones. HOW ARE GALLSTONES TREATED? – There are three general options for people with gallstones; the best option depends upon the clinical setting: • Expectant management: Do nothing, wait and watch. • Surgical therapy: Removal of the gallbladder with its stones. • Non-surgical therapy: Elimination of the stones while preserving the gallbladder People with asymptomatic gallstones – People with gallstones who are asymptomatic usually require no specific intervention. As mentioned above, silent stones do not need to be treated since the initial symptoms are usually mild. Experts feel that the risk from surgical removal of the gallbladder is greater than the risk from not treating silent stones. Thus, preventive gallbladder removal in asymptomatic gallstones is not recommended since many such individuals will remain asymptomatic for a very long time, possibly even for the rest of their lives. Individuals with silent gallstones must be educated as to the initial symptoms of gallstone disease because treatment should be sought once the first symptoms occur since the chance of recurrent and more severe symptoms becomes very high. WHAT ARE THE SURGICAL TREATMENT OPTIONS? – The gallbladder is an important organ, but is not essential for life. Therefore, the standard treatment for symptomatic patients who suffer from gallstones has been to have the gallbladder removed surgically along with its contained stones. Removing the gallbladder may have little or no effect on digestion. Loose stools, gas, and bloating may develop in about half the patients, but in most they are mild, requiring no dietary restrictions after the gallbladder is removed. Open cholecystectomy – Cholecystectomy, surgical removal of the gallbladder, is one of the most commonly performed surgical procedures; more than 700,000 are performed in the United States each year. There are two versions of this operation. The first is the classic open cholecystectomy which leaves a 4- to 6-inch scar and usually requires three to five days of hospitalization and several weeks of recuperation. The operation is extremely safe (complications occurring in only 6 percent of patients but major complications are very rare). However, the risk increases with age and in patients with other medical problems. Laparoscopic cholecystectomy – The second and newer surgical technique is laparoscopic cholecystectomy. Under general anesthesia, a video-endoscope and instruments are introduced into the abdomen through four or five very small non-muscle cutting incisions and used to visualize and remove the gallbladder. The patient is typically hospitalized for one to two days and requires a recovery time of one to two weeks. Over the past few years laparoscopic cholecystectomy quickly became the standard operation for removing the gallbladder. Experience with this technique has shown this operation to be safe and well tolerated by the patient but the chance of complications relating to common bile duct injury is somewhat higher than that of the other procedure. Most cholecystectomies are now performed laparoscopically. However, both open and laparoscopic approaches may have particular advantages in certain situations. For example, laparoscopic cholecystectomy may not always be possible in emergency settings and in about 5 to 10 percent of patients a laparoscopic operation has to be converted to an open cholecystectomy during the surgery for a variety of reasons. Physicians, surgeons, and other members of the healthcare team will recommend the most appropriate method for a patient's particular clinical situation. There have been reports of an increase in the risk of colon cancer in patients whose gallbladders have been removed. This is thought to be due to the chronic leakage of bile into the colon in patients who do not have a gallbladder. However, experts feel that studies are conflicting and inconclusive. If anything there may be a slight increase in the risk of right-sided colon cancer as reported in some studies. WHAT NON-SURGICAL TREATMENT OPTIONS ARE AVAILABLE?– Nonsurgical approaches are available for the treatment of gallstones. These require no surgical incision or general anesthesia and eliminate the stones while preserving the gallbladder. Four non-surgical approaches are currently available for the treatment of gallstones. Oral bile acid pill –. It contains a natural bile acid that slowly dissolves predominantly cholesterol gallstones over a period of one to three years. However, about two-thirds of patients become symptom free about two to three months after the bile acid pill is started and remain as such even though it may take several years for the stones to actually disappear. Nevertheless, because of its slow action its use is not practical in patients with recurrent or acute symptoms. It is very safe and well tolerated, but mild transient diarrhea may occur in a minority of patients. Its use is limited to small cholesterol stones, it requires a functioning gallbladder, and is typically effective in only 50 percent of patients who are qualified to take it. Topical gallstone dissolution – The second non-surgical approach is topical gallstone dissolution, which is not approved and still in the investigational stages in the United States. It involves dissolving the stones by bathing them with a gallstone dissolving solution (solvent). At the present time it is limited only to gallstones that are mostly cholesterol by composition as determined by a specialized CT-scan. For this procedure, a small tube (catheter) about the size of a strand of spaghetti is inserted into the gallbladder through a tiny needle puncture while the patient is under local anesthesia. The catheter is then used to instill the solvent, which is used to irrigate the gallbladder and dissolve the stones. This would typically take a few hours to complete after which the solvent is evacuated from the gallbladder and the patient goes home and returns a few days later to have the catheter removed. While the patient is at home, the catheter is comfortably taped to the skin and does not normally affect the patient's daily activities or work. Because of its rapid action and because it does not require general anesthesia or significant recuperation time, it is especially desirable for the treatment of patients who are at higher risk of complications from surgery or general anesthesia. Percutaneous endoscopic laser or electrohydraulic lithotripsy – The third non-surgical approach is Percutaneous endoscopic laser or electrohydraulic lithotripsy. In this procedure, a catheter is inserted into the gallbladder under local anesthesia and remains in place for two weeks. The patient would then return when the catheter track is slightly enlarged to the size of a small straw. A laser probe is then used to apply short bursts of laser energy to fracture the stones into small pieces that are then washed out of the gallbladder. The devices for this procedure are currently approved and available in the United States and it is the only non-surgical approach that is effective for all types of stones. Thus, it is useful for non-cholesterol pigment stones. The main disadvantage is that it is a prolonged procedure requiring three to four outpatient visits over several weeks for completion. It is also labor intensive and, therefore, rarely done only on patients at high-risk who have non-cholestesterol stones. Extracorporeal shock wave lithotripsy – The fourth approach is extracorporeal shock wave lithotripsy (ESWL). Shock waves generated outside the body are focused on the gallstones to fracture them into smaller fragments and "sand," which can then be dissolved more efficiently by the oral bile acid pill. ESWL has been approved and used extensively in the treatment of kidney stones. It was recently approved for the treatment of gallstones as well. Since it relies on bile acid therapy to clear the fractured stones and residue, it can only treat cholesterol stones. It is not effective for more than three stones or large stones and a functioning gallbladder is required. Studies to date show that its success rate is not very high and may be painful, necessitating sedation. It may also cause attacks of biliary pain as fragments pass through the bile duct into the intestine. The shock waves may cause some internal organ damage, which usually is not significant. Gallstone recurrence – The main disadvantage of any of the non-surgical treatment options is that since the gallbladder is not removed, gallstone recurrence is possible. With oral therapy, stones appear to recur in only 50 percent of patients and typically only in the first five years. Generally, it takes many years for the recurrent stones to grow. Even if stones recur, most patients will continue to be symptom free because studies show that gallstone symptoms develop at a low rate of 1 to 2 percent per year. GALLSTONE PREVENTION – Some doctors recommend the following to help prevent the development of gallstones: • Consumption of three well balanced meals daily, with each meal containing some fat to ensure good gallbladder contraction. This would prevent stagnation in the gallbladder, which is one of the factors of gallstone formation in susceptible individuals. • Maintenance of a diet that is high in fiber and calcium and low in saturated fats. • Maintenance of a normal standard body weight through proper calorie restriction and regular, appropriate exercise. Obese people (with and without known gallstones) who are undergoing a rapid weight-loss program should be supervised by their physician and may require specific treatment with oral bile acids to prevent the development of gallstones during weight loss.