What are gallstones?
Gallstones, which are created in the gallbladder, form when substances in the bile create hard, crystal-like particles. Cholesterol stones, as the name implies, are made of cholesterol and appear light in color. Eighty percent of gallstones are formed this way.
Pigment stones are small, dark stones made of bilirubin and calcium salts that are found in bile. About twenty percent of gallstones are pigment stones. Risk factors for pigment stones include:
- cirrhosis of the liver
- biliary tract infections
- hereditary blood cell disorders (such as sickle cell anemia)
Gallstones can be as small as a grain of salt or as large as a golf ball. The gallbladder may develop many smaller stones, or a single, often large, one. It may even develop several thousand stones.
What are bile duct stones?
Gallstones that move out of the gallbladder can pass into your stomach. However, a stone may become lodged in your bile duct due to the size of the stone or the anatomy of the biliary tree. Bile duct stones are gallbladder stones that have become lodged in the bile duct. Stones that become stuck in the ducts that lead to the duodenum can be both agonizing and dangerous.
What causes gallstones?
Advancements have been made in better understanding the gallstone formation process. Gallstones may be caused by:
- inherited body chemistry
- body weight
- gallbladder movement (the gallbladder is a muscular sack that contracts)
- diet and lifestyle
When the bile contains too much cholesterol and not enough bile salts, cholesterol gallstones may develop. Aside from a high concentration of cholesterol, there are two other factors that seem to be of importance in causing gallstones. Movement of the gallbladder is refered to as gallbladder motility. This small but muscular organ squeezes to force bile into the bile duct. If the gallbladder does not perform as it should, the bile may not be able to makes its way into the bile duct, instead becoming concentrated and forming small crystals.
Gallstones may also be created by proteins in the liver and bile. These proteins may either promote cholesterol crystallization into gallstones.
Other factors also seem to play a role in causing gallstones but how is not clear.
- Low calorie, and rapid weight-loss diets
- Prolonged fasting
- Increased levels estrogen as a result of pregnancy
- Hormone therapy
- Birth control pills
No clear relationship has been proven between gallstone formation and a particular diet.
Who is at risk for gallstones?
Gallstones affect approximately one million people every year, with women being twice as likely to become afflicted than men. They will join the estimated 20 million Americans —roughly 10 percent of the population— who already have gallstones.
Those who are most likely to develop gallstones are:
- Women, ages 20 – 60
- Men and women, ages 60+
- Men and women who are overweight
- Men and women who go on “crash” diets or who lose of lot of weight quickly
- Pregnant women, or women who have used birth control pills or estrogen replacement therapy
- Native Americans
What are the symptoms of gallstones?
A person with gallstones may have what are called “silent stones”. Studies show that most people with silent stones may not experience any symptoms at all for awhile, remaining symptom-free for years and requiring no treatment. Silent stones may go undiagnosed until they begin to cause discomfort.
For those that are not quite so lucky, the symptoms my include:
- Acute pain, possibly very severe, that occurs very suddenly. It may last a few minutes, or many hours
- Pain is usually located behind your breastbone, but may occur in the upper right abdominal area
- Pain between your shoulder-blades is another symptom of gallstones
- Chills and fever
- Jaundice (a condition in which the skin and eyes develop a yellow pallor)
- Nausea and vomiting
It is not uncommon for attacks to be separated by weeks, months, or even years.
What problems can occur?
A common complication cause by gallstones is blockage of the cystic duct. Sometimes gallstones may make their way out of the gallbladder and into the cystic duct, the channel through which bile travels from the gallbladder to the small intestine. An inflammation of the gallbladder (cholecystitis) can occur if the flow of bile in the cystic duct is severly impeded or blocked by any gallstones.
A less common but more serious problem occurs if the gallstones become lodged in the bile ducts between the liver and the intestine. This condition, called cholangitis, can block bile flow from the gallbladder and liver, causing pain, jaundice and fever.
Gallstones may also interfere with the flow of digestive fluids into the small intestine, leading to an inflammation of the pancreas, or pancreatitis. Prolonged blockage of any of these ducts can cause severe damage to the gallbladder, liver, or pancreas which can be fatal.
How are gallstones diagnosed?
Diagnostic methods for detecting gallstones may include:
- abdominal X-ray,
- computerized axial tomography (CT) scan, or
- abdominal ultrasound that has been taken for an unrelated problem or complaint.
When actually looking for gallstones, the most common diagnostic tool is ultrasound. An ultrasound examination, also known as ultrasonography, uses sound waves to create images of the various abdominal organs .. including the gallbladder. If stones are present, the sound waves will bounce off the stones, revealing their location.
Occassionaly, other tests needed to detect small stones, or verify their non-existance, may be required.
- MRCP uses a magnetic imaging technique. It is painless.
- Endoscopic Ultrasound is a minimally invasive procedure that can visualize tissue near the esophagus and stomach
- ERCP is particularly relevant for diagnosis and management of stones in the bile duct.