Gallstone
Gallstones, medically known as cholelithiasis, are hard, rock-like particles that form in the gallbladder, a small organ that stores bile produced by the liver. They can vary in size and number and range from tiny grains to large stones. Gallstones are particularly prevalent in the United States, affecting an estimated 10–15 percent of adults, with higher rates among women, senior citizens, and specific ethnic groups such as American Indians and Mexican Americans. Two main types of gallstones exist: cholesterol stones, which are yellowish and account for over 80% of cases, and pigment stones, which are typically dark brown and form from crystallized bilirubin.
While many individuals with gallstones experience no symptoms, some may suffer from intense abdominal pain, especially after eating fatty meals. Symptoms can include nausea, indigestion, fever, and jaundice. Diagnosis often involves ultrasound imaging to distinguish gallstones from other gastrointestinal issues. Treatment typically involves surgical removal of the gallbladder, a common and generally safe procedure, though medications to dissolve stones are available as a last resort. Notably, genetic factors, such as mutations in the ABCG8 gene, can increase the likelihood of developing gallstones, offering insight into the condition’s varying prevalence across different populations.
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Gallstone
Gallstones (known medically as cholelithiasis) are hard, rock-like particles that form within the gallbladder and may become lodged into the passageways that lead from the gallbladder to the pancreas or small intestine. Gallstones are fairly common in the United States, as an estimated 10–15 percent of all American adults have developed gallstones. However, gallstones are disproportionately more common among certain groups than others. Women are more likely to develop gallstones than men, and gallstones are much more common among senior citizens than among younger people. Certain American Indian ethnic groups and Mexican Americans have higher rates of gallstones. Furthermore, persons who are overweight or obese are much more likely to develop gallstones than persons who maintain an average body weight. Although gallstones may sound like a serious medical condition—and although gallstones can lead to intense pain in individuals—gallstones are usually not harmful or life-threatening, and they can usually be treated easily.
Background
Gallstones form in the gallbladder, which is a small pouch located on the right side of the abdomen. The gallbladder is approximately the size and shape of a pear, and it is positioned between the liver and pancreas. The purpose of the gallbladder is to store bile, a liquid that is produced by the liver and allows the body to digest the fats in food. When eating fatty substances, the gallbladder releases bile to aid in digestion. The amount of bile that the gallbladder releases is relative to the level of fatty content in the food consumed. Bile consists of a mix of cholesterol, bilirubin (the pigment found in bile), and salts. Gallstones develop when this chemical balance of bile is distorted. Three different specific types of gallstones may develop, with the two most common types known as cholesterol stones and pigment stones. Cholesterol stones form when there is an excessive amount of cholesterol in the bile, and the extra cholesterol crystallizes and hardens into a stone-like structure. Pigment stones form when bilirubin crystallizes. Cholesterol stones are yellowish in color, while pigment stones are typically dark brown. Of these two types, cholesterol stones are far more common and account for over 80 percent of gallstone diagnoses in the United States. Scientists and medical researchers still do not known exactly what causes the chemical imbalances in bile that lead to the formation of gallstones.
Gallstones vary in their size, shape, and number. They range in size from a tiny grain of sand to that of a small rubber ball. Furthermore, some individuals develop a single large gallstone, while others develop many tiny gallstones. Gallstones often do not cause pain, and many people may have gallstones without being aware. Only about 1–3 percent of Americans visit the hospital for gallstone-related pains each year, even though an estimated 20–25 million Americans have gallstones. Nevertheless, some gallstones can cause intense pain in the upper-right abdomen, chest, shoulder, or back (known as a gallbladder attack or biliary colic). These pains typically strike after eating a meal and may last from 15 minutes to an hour or longer. In addition to stomach pains, other symptoms of gallstones include indigestion, nausea, fever, yellowish skin and/or eyes (called jaundice), or dark urine.
Overview
Since the symptoms of gallstones are very similar to that of other gastrointestinal disorders, such as hepatitis and liver disease, a gastroenterologist (a doctor who specializes in the digestive system) usually conducts an ultrasound scan of the abdomen to identify if gallstones are present. Typically, doctors will not treat gallstones unless the condition causes pain or other problems in patients. By far the most common method of treating gallstones is to remove them through surgery, although certain medicines are available to break down gallstones over time. However, doctors prefer surgery because it is quicker and relatively safe. Surgery consists of removing the gallbladder from the patient. Interestingly, this is not a dangerous procedure because bile is not produced by the gallbladder—it is only stored there until it is needed for digestion. When the gallbladder is removed, bile is released from the liver directly to the small intestine with little-to-no side effects in patients (and even these minor side effects, should they occur usually subside within a few weeks of the procedure). Doctors only issue medicines (ursodiol and chenodiol) as a last resort, if surgery would pose a serious risk to a patient. Patients using medicine must take it two to three times daily. These medicines can take up to six months to break down a small gallstone, while a larger gallstone may take one to two years. Furthermore, unless the gallbladder is removed, gallstones will redevelop within five years.
Surgery to remove gallbladders has become one of the most common types of surgery performed in the United States, with approximately 500,000 Americans undergoing this procedure annually. With an increased understanding of genetics, scientists have identified that a mutation (a random change in one’s DNA) of the ABCG8 gene, which is located on second chromosome of humans, greatly increases a person’s chance of developing gallstones. This may, at least in part, account for the higher rates of gallstones among certain American Indian groups and Mexican Americans, although gallstones can develop in persons of all ethnic backgrounds. Roughly 60 percent of American Indian women and 30 percent of American Indian men develop gallstones, while the rate is approximately 15 percent for white Americans of northern European ancestry. Women are at a greater risk of developing gallstones than men because of their higher levels of estrogen, and pregnant women are more likely to develop gallstones than non-pregnant women.
Bibliography
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