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Julio Alejandro Murra-Saca MD.
Gastroenterologist,
Tel : (503) 226-3131, (503) 225-3087, Celular (503) 887-2507
Email
 
Edificio Centro Scan, Colonia Médica, San Salvador, El Salvador.

 

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Notes on Cyber Gastroenterology

 

Cholelithiasis (Gallstones)
What Are Gallstones?
Gallstones form when liquid called bile is stored in the gallbladder hardens into pieces of stone-like material. The bile, is used to help the body digest fats. Bile is made in the liver, then stored in the gallbladder until the body needs to digest fat. At that time, the gallbladder contracts and pushes the bile into a tube—called a duct—that carries it to the small intestine, where it helps with digestion.

Bile is a brown liquid which contains bile salts, cholesterol, bilirubin, and lecithin. About three cups are produced by the liver every day. Some substances in bile, including bile salts and lecithin, act like detergents to break up fat so that it can be easily digested. Others, like bilirubin, are waste products. Bilirubin is a dark brown substance which gives a brown color to both bile and to stool

If the liquid bile contains too much cholesterol, bile salts, or bilirubin, it can harden into stones. The two types of gallstones are cholesterol stones and pigment stones. Cholesterol stones are usually yellow-green and are made primarily of hardened cholesterol. They account for about 80 percent of gallstones. Pigment stones are small, dark stones made of bilirubin. Some gallstones are tiny ; as small as a grain of sand; others reach the size of a golf ball. Some people have only one stone; others develop hundreds.



The gallbladder and the ducts that carry bile and other digestive enzymes from the liver, gallbladder, and pancreas to the small intestine are called the biliary system.
   

The gallbladder and the ducts that carry bile and other digestive enzymes from the liver, gallbladder, and pancreas to the small intestine are called the biliary system. Gallstones can block the normal flow of bile if they lodge in any of the ducts that carry bile from the liver to the small intestine. That includes the hepatic ducts, which carry bile out of the liver; the cystic duct, which takes bile to and from the gallbladder; and the common bile duct, which takes bile from the cystic and hepatic ducts to the small intestine. Bile trapped in these ducts can cause inflammation in the gallbladder, the ducts, or, rarely, the liver. Other ducts open into the common bile duct, including the pancreatic duct, which carries digestive enzymes out of the pancreas.

Symptoms: Severe, steady (not fluctuating) pain in the upper right abdomen, which may spread to include the chest, back (between the shoulder blades) and shoulders; this pain may last as little as 15 minutes or as long as several hours; you may feel a repeat episode of pain a few hours later, or it may take weeks, months or even years for another attack to occur. Nausea Vomiting Sweating Jaundice (yellowing of the skin and whites of the eyes). Many people have "silent" gallstones and may experience no symptoms for months or years or even a lifetime.
Biliary colic is an extremely severe pain in the upper right-hand part of the abdomen. The pain, which comes and goes, is often accompanied by sweating and vomiting. It is the result of a spasm of the gall bladder or of obstruction of the bile ducts, either of which is caused by one or more gallstones.
If a gallstone blocks the opening to that duct
, digestive enzymes can become trapped in the pancreas and cause an extremely painful inflammation called pancreatitis. If any of these ducts remain blocked for a significant period of time, severe—possibly fatal—damage can occur, affecting the gallbladder, liver, or pancreas. Warning signs of a serious problem are fever, jaundice, and persistent pain.
In rare cases, a gallstone may erode through the wall of the gallbladder, enter the intestine and migrate to the wall of the ileocecal valve, the point at which the small and large intestines meet. This is called a gallstone ileus, and it may result in bowel obstruction, another very serious and potentially life-threatening event requiring emergency treatment.


What Causes Gallstones? Cholesterol Stones Scientists believe cholesterol stones form when bile contains too much cholesterol, too much bilirubin, or not enough bile salts, or when the gallbladder does not empty as it should for some other reason. Pigment Stones The cause of pigment stones is uncertain. They tend to develop in people who have cirrhosis, biliary tract infections, and hereditary blood disorders such as sickle cell anemia. Other Factors It is believed that the mere presence of gallstones may cause more gallstones to develop. However, other factors that contribute to gallstones have been identified, especially for cholesterol stones. Obesity. Obesity is a major risk factor for gallstones, especially in women. A large clinical study showed that being even moderately overweight increases one's risk for developing
moderately overweight increases one's risk for developing gallstones. The most likely reason is that obesity tends to reduce the amount of bile salts in bile, resulting in more cholesterol. Obesity also decreases gallbladder emptying. Estrogen. Excess estrogen from pregnancy, hormone replacement therapy, or birth control pills appears to increase cholesterol levels in bile and decrease gallbladder movement, both of which can lead to gallstones. Ethnicity. Native Americans have a genetic predisposition to secrete high levels of cholesterol in bile. In fact, they have the highest rates of gallstones in the United States. A majority of Native American men have gallstones by age 60. Among the Pima Indians of Arizona, 70 percent of women have gallstones by age 30. Mexican-American men and women of all ages also have high rates of gallstones. Gender. Women between 20 and 60 years of age are twice as likely to develop gallstones as men. Age. People over age 60 are more likely to develop gallstones than younger people. Cholesterol-lowering drugs. Drugs that lower cholesterol levels in blood actually increase the amount of cholesterol secreted in bile. This in turn can increase the risk of gallstones. Diabetes. People with diabetes generally have high levels of fatty acids called triglycerides. These fatty acids increase the risk of gallstones. Rapid weight loss. As the body metabolizes fat during rapid weight loss, it causes the liver to secrete extra cholesterol into bile, which can cause gallstones. Fasting. Fasting decreases gallbladder movement, causing the bile to become overconcentrated with cholesterol, which can lead to gallstones. Who Is at Risk for Gallstones? Women. People over age 60. Native Americans. Mexican-Americans. Overweight men and women. People who fast or lose a lot of weight quickly. Pregnant women, women on hormone therapy, and women who use birth control pills. What are the Symptoms? Symptoms of gallstones are often called a gallstone "attack" because they occur suddenly. A typical attack can cause Steady, severe pain in the upper abdomen that increases rapidly and lasts from 30 minutes to several hours. Pain in the back between the shoulder blades. Pain under the right shoulder. Nausea or vomiting. Gallstone attacks often follow fatty meals, and they may occur during the night. Other gallstone symptoms include Abdominal bloating. Recurring intolerance of fatty foods. Colic. Belching. Gas. Indigestion. People who also have the following symptoms should see a doctor right away: Sweating. Chills. Low-grade fever. Yellowish color of the skin or whites of the eyes. Clay-colored stools. Many people with gallstones have no symptoms. These patients are said to be asymptomatic, and these stones are called "silent stones." They do not interfere in gallbladder, liver, or pancreas function and do not need treatment.


How Are Gallstones Diagnosed? millions of people, gallstones are "silent," never causing symptoms. Many people may not be aware that they have gallstones; gallstones are often discovered incidentally, during diagnostic tests for other conditions. But when gallstones are suspected to be the cause of symptoms, the doctor is likely to do an ultrasound exam.

Ultrasound exam.

Ultrasound uses sound waves to create images of organs. Sound waves are sent toward the gallbladder through a handheld device that a Radiologist glides over the abdomen. The sound waves bounce off the gallbladder, liver, and other organs, and their echoes make electrical impulses that create a picture of the organ on a video monitor. If stones are present, the sound waves will bounce off them, too, showing their location. Other tests used in diagnosis include Cholecystogram or cholescintigraphy. The patient is injected with a special iodine dye, and x-rays are taken of the gallbladder over a period of time. (Some people swallow iodine pills the night before the x-ray.) The test shows the movement of the gallbladder and any obstruction of the cystic duct.
Endoscopic retrograde cholangiopancreatography (ERCP). The patient swallows an endoscope—a long, flexible, lighted tube connected to a computer and TV monitor. The Gastroenterologist guides the endoscope through the stomach and into the small intestine. The doctor then injects a special dye that temporarily stains the ducts in the biliary system. ERCP is used to locate stones in the ducts. Blood tests. Blood tests may be used to look for signs of infection, obstruction, pancreatitis, or jaundice. Gallstone symptoms are similar to those of heart attack, appendicitis, ulcers, irritable bowel syndrome, hiatal hernia, pancreatitis, and hepatitis. So accurate diagnosis is important. What is the Treatment? Surgery Surgery to remove the gallbladder is the most common way to treat symptomatic gallstones. (Asymptomatic gallstones usually do not need treatment.) Each year more than 500,000 Americans have gallbladder surgery. The surgery is called cholecystectomy. The standard surgery is called laparoscopic cholecystectomy. For this operation, the surgeon makes several tiny incisions in the abdomen and inserts surgical instruments and a miniature video camera into the abdomen. The camera sends a magnified image from inside the body to a video monitor, giving the surgeon a closeup view of the organs and tissues. While watching the monitor, the surgeon uses the instruments to carefully separate the gallbladder from the liver, ducts, and other structures. Then the cystic duct is cut and the gallbladder removed through one of the small incisions.

Because the abdominal muscles are not cut during laparoscopic surgery, patients have less pain and fewer complications than they would have had after surgery using a large incision across the abdomen. Recovery usually involves only one night in the hospital, followed by several days of restricted activity at home. If the surgeon discovers any obstacles to the laparoscopic procedure, such as infection or scarring from other operations, the operating team may have to switch to open surgery. In some cases the obstacles are known before surgery, and an open surgery is planned. It is called "open" surgery because the surgeon has to make a 5- to 8-inch incision in the abdomen to remove the gallbladder. This is a major surgery and may require about a 2- to 7-day stay in the hospital and several more weeks at home to recover. Open surgery is required in about 5 percent of gallbladder operations. The most common complication in gallbladder surgery is injury to the bile ducts. An injured common bile duct can leak bile and cause a painful and potentially dangerous infection. Mild injuries can sometimes be treated nonsurgically. Major injury, however, is more serious and requires additional surgery. If gallstones are in the bile ducts, the surgeon may use ERCP in removing them before or during the gallbladder surgery. Once the endoscope is in the small intestine, the surgeon locates the affected bile duct. An instrument on the endoscope is used to cut the duct, and the stone is captured in a tiny basket and removed with the endoscope. This two-step procedure is called ERCP with endoscopic sphincterotomy. Occasionally, a person who has had a cholecystectomy is diagnosed with a gallstone in the bile ducts weeks, months, or even years after the surgery. The two-step ERCP procedure is usually successful in removing the stone. Nonsurgical Treatment Nonsurgical approaches are used only in special situations—such as when a patient's condition prevents using an anesthetic—and only for cholesterol stones. Stones recur after nonsurgical treatment about half the time. Oral dissolution therapy. Drugs made from bile acid are used to dissolve the stones. The drugs, ursodiol (Actigall) and chenodiol (Chenix), work best for small cholesterol stones. Months or years of treatment may be necessary before all the stones dissolve. Both drugs cause mild diarrhea, and chenodiol may temporarily raise levels of blood cholesterol and the liver enzyme transaminase. Contact dissolution therapy. This experimental procedure involves injecting a drug directly into the gallbladder to dissolve stones. The drug—methyl tert butyl—can dissolve some stones in 1 to 3 days, but it must be used very carefully because it is a flammable anesthetic that can be toxic. The procedure is being tested in patients with symptomatic, noncalcified cholesterol stones. Extracorporeal shockwave lithotripsy (ESWL). This treatment uses shock waves to break up stones into tiny pieces that can pass through the bile ducts without causing blockages. Attacks of biliary colic (intense pain) are common after treatment, and ESWL's success rate is not very high. Remaining stones can sometimes be dissolved with medication. Don't People Need Their Gallbladders? Fortunately, the gallbladder is an organ that people can live without. Losing it won't even require a change in diet. Once the gallbladder is removed, bile flows out of the liver through the hepatic ducts into the common bile duct and goes directly into the small intestine, instead of being stored in the gallbladder. However, because the bile isn't stored in the gallbladder, it flows into the small intestine more frequently, causing diarrhea in some people. Also, some studies suggest that removing the gallbladder may cause higher blood cholesterol levels, so occasional cholesterol tests may be necessary.


Points To Remember
Gallstones form when substances in the bile harden.
Gallstones are common among women, Native Americans, Mexican-Americans, and people who are overweight.
Gallstone attacks often occur after eating a fatty meal. Symptoms can mimic those of other problems, including heart attack, so accurate diagnosis is important.
Gallstones can cause serious problems if they become trapped in the bile ducts.
Laparoscopic surgery to remove the gallbladder is the most common treatment.

Cholecystitis
Cholecystitis is defined as inflammation of the gallbladder that occurs most commonly because of obstruction of the cystic duct from cholelithiasis. Ninety percent of cases involve stones in the cystic duct (ie, calculous cholecystitis), with the other 10% representing acalculous cholecystitis. Although bile cultures are positive for bacteria in 50-75% of cases, bacterial proliferation may be a result of cholecystitis and not the precipitating factor. Risk factors for cholecystitis mirror those for cholelithiasis and include increasing age, female sex, certain ethnic groups, obesity or rapid weight loss, drugs, and pregnancy.
Acalculous cholecystitis is related to conditions associated with biliary stasis, including debilitation, major surgery, severe trauma, sepsis, long-term total parenteral nutrition (TPN), and prolonged fasting. Other causes of acalculous cholecystitis include cardiac events; sickle cell disease; Salmonella infections; diabetes mellitus; and cytomegalovirus, cryptosporidiosis, or microsporidiosis infections in patients with AIDS.

History:

The most common presenting symptom of acute cholecystitis is upper abdominal pain, often radiating to the tip of the right scapula.
Most patients with acute cholecystitis describe a history of biliary pain. Some patients may have documented gallstones. Acalculous biliary colic also occurs, most commonly in young–to–middle-aged females. The presentation is almost identical to calculous biliary colic with the exception of reference range laboratory values and no findings of cholelithiasis on ultrasound.
Frequently, the pain begins in the epigastric region and then localizes to the right upper quadrant (RUQ). Although the pain may initially be described as colicky, it becomes constant in virtually all cases.
Signs of peritoneal irritation may be present, and, in some patients, the pain may radiate to the right shoulder or scapula.
Nausea and vomiting are generally present, and patients may report fever.
In elderly patients, pain and fever may be absent, and localized tenderness may be the only presenting sign. Patients with acalculous cholecystitis may present similarly to patients with calculous cholecystitis, but acalculous cholecystitis frequently occurs suddenly in severely ill patients without a prior history of biliary colic. Often, patients with acalculous cholecystitis may present with fever and sepsis alone, without history or physical examination findings consistent with acute cholecystitis.
Cholecystitis is differentiated from biliary colic by the persistence of constant severe pain for more than 6 hours

Physical
Physical examination may reveal fever, tachycardia, and tenderness in the RUQ or epigastric region, often with guarding or rebound.
A palpable gallbladder or fullness of the RUQ is present in 30-40% of cases.
Jaundice may be noted in approximately 15% of patients.
The absence of physical findings does not rule out the diagnosis of cholecystitis. Many patients present with diffuse epigastric pain without localization to the RUQ. Patients with chronic cholecystitis frequently do not have a palpable RUQ mass secondary to fibrosis involving the gallbladder.
Elderly patients and patients with diabetes frequently have atypical presentations, including absence of fever and localized tenderness with only vague symptoms.
Murphy sign, which is specific but not sensitive for cholecystitis, is described as tenderness and an inspiratory pause elicited during palpation of the RUQ.
 
Biliary colic represents one of the causes of epigastric pain and is the most common presentation of symptomatic gallstone disease (cholelithiasis/choledocholithiasis). Because this is a symptom, numerous other disease processes may result in pain that is similar to biliary colic. These disease processes should be considered during the evaluation of patients being considered to have biliary colic. The pain of biliary colic is listed inaccurately as a colic because this term implies a paroxysmal pain that is waxing and waning in nature. This often is not the case.

Careful history and examination are cornerstones to making an accurate clinical diagnosis, essentially because of the high incidence of gallstones in the population and because most gallstones are asymptomatic. The potential disastrous implications of a misdiagnosis as biliary colic instead of alternative diagnoses that may present with epigastric pain (eg, atypical myocardial ischemia) cannot be overemphasized. Patients also can be particularly unhappy and frustrated when their pain is not resolved following cholecystectomy. The differential diagnosis section lists other important medical conditions one should consider in patients who present with possible biliary colic (see Differentials).

History should elicit the nature, intensity, location, duration, onset, cessation, associated factors, aggravating factors, relieving factors, radiation, and frequency (NILDOCARRF) of the pain (see History). At the same time, one should evaluate risk factors for stone formation while addressing potentially confounding factors such as medical comorbidities (eg, cardiovascular disease).

This visceral pain is believed to result from impaction of a gallstone in the cystic duct and/or ampulla of Vater, causing distension of the gallbladder and/or biliary tract; this activates visceral afferent sensory neurons. The pain commonly is localized poorly and referred midline to representative dermatomes T8/9 (mid epigastrium, right upper quadrant). Localized pain generally represents a complication of cholelithiasis or choledocholithiasis (eg, cholecystitis, cholangitis, pancreatitis).

Biliary colic is the presenting symptom in 80% of patients with gallstone disease who seek medical care; however, only 10-20% of all individuals with gallstones experience severe gallstone pain. The risk of developing biliary pain or stone-related complications in asymptomatic patients is low, at 1-2% per year. For this reason, clinical practice favors treatment of only symptomatic disease, with the exception of a few unique circumstances. Two thirds of patients presenting with their first attack of biliary colic have recurrent pain within 2 years.


Pathophysiology: A gallstone produces visceral pain by obstructing the cystic duct or ampulla of Vater, resulting in distention of the gallbladder or biliary tree. Pain is relieved when the gallstone migrates back into the gallbladder, passes through the ampulla, or falls back into the common bile duct (CBD). The pain of biliary colic may accompany sphincter of Oddi spasm.

 

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