Cholecystitis is inflammation of the gallbladder, usually resulting from a gallstone blocking the cystic duct. The gall bladder assists in the digestive process by storing and releasing the substance called bile into the small intestine, which helps break down food.
Cholecystitis is classified as acute or chronic.
- Acute Cholecystitis: At least 95% of people with acute cholecystitis have gallstones. The inflammation almost always begins without infection, although infection may follow later. Inflammation may cause the gallbladder to fill with fluid and its walls to thicken. Rarely, a form of acute cholecystitis without gallstones (acalculous cholecystitis) occurs. Acalculous cholecystitis is more serious than other types of cholecystitis.
- Chronic Cholecystitis: Chronic cholecystitis is gallbladder inflammation that has lasted a long time. It almost always results from gallstones. It is characterized by repeated attacks of pain (biliary colic). In chronic cholecystitis, the gallbladder is damaged by repeated attacks of acute inflammation, usually due to gallstones, and may become thick-walled, scarred, and small. The gallbladder usually contains sludge (microscopic particles of materials similar to those in gallstones) or gallstones that block its opening into the cystic duct or reside in the cystic duct itself.
A gallbladder attack, whether in acute or chronic cholecystitis, begins as pain. The pain of cholecystitis is similar to that caused by gallstones but is more severe and lasts longer—more than 6 hours and often more than 12 hours. The pain peaks after 15 to 60 minutes and remains constant. It usually occurs in the upper right part of the abdomen. The pain may become excruciating.
Most people feel a sharp pain when a doctor presses on the upper right part of the abdomen. Breathing deeply may worsen the pain. The pain often extends to the lower part of the right shoulder blade or to the back. Nausea and vomiting are common.
Within a few hours, the abdominal muscles on the right side may become rigid. Fever occurs in about one third of people with acute cholecystitis. The fever tends to rise gradually to above 100.4° F (38° C) and may be accompanied by chills. Fever rarely occurs in people with chronic cholecystitis.
In older people, the first or only symptoms of cholecystitis may be rather general. For example, older people may lose their appetite, feel tired or weak, or vomit. They may not develop a fever.
Typically, an attack subsides in 2 to 3 days and completely resolves in a week. If the acute episode persists, it may signal a serious complication. A high fever, chills, a marked increase in the white blood cell count and cessation of the normal rhythmic contractions of the intestine suggest pockets of pus (abscesses) in the abdomen near the gallbladder or a perforated gallbladder.
If people develop jaundice or pass dark urine and light-colored stools, the common bile duct is probably blocked by a stone, causing a backup of bile in the liver (cholestasis). Inflammation of the pancreas (pancreatitis) can develop.
Acalculous cholecystitis typically causes sudden, excruciating pain in the upper abdomen in people with no previous symptoms or other evidence of a gallbladder disorder. The inflammation is often very severe and can lead to rupture of the gallbladder. In people with other severe problems, acalculous cholecystitis may be overlooked at first. The only symptoms may be a swollen (distended), tender abdomen or a fever with no known cause.
Cholecystitis is caused by multiple factors, including obstruction of a bile duct by gallstones, infection, injury, or tumor. The most common cause of cholecystitis is cholelithiasis, or gallstones, that cause obstructions in the bile ducts. Cholecystitis caused by infection, trauma and tumors can result in possible blockage and perforation of the gallbladder.
When acute cholecystitis occurs, it may interfere with the flow of bile and cause bile to become trapped in the gallbladder, resulting in inflammation and possible bacterial infection. In rare cases, perforation of the gallbladder is also possible. Chronic cholecystitis is commonly caused by recurring episodes of acute cholecystitis, resulting in thickening of the gallbladder walls and a loss of gallbladder function.
A number of factors increase the risk of developing cholecystitis. Not all people with risk factors will get cholecystitis. Risk factors for cholecystitis include:
- Age over 40 years.
- Female gender.
- Injury to the gallbladder.
- Overweight or obesity.
People who have gallstones but don't have any symptoms may need no treatment. For mild cases, treatment includes bowel rest, fluids and antibiotics given through a vein, and pain medicine.
The main treatment for acute cholecystitis is surgery to remove the gallbladder (cholecystectomy). Often this surgery can be done through small incisions in the abdomen (laparoscopic cholecystectomy), but sometimes it requires a more extensive operation.
Your doctor may try to reduce swelling and irritation in the gallbladder before removing it. Sometimes acute cholecystitis is caused by one or more gallstones getting stuck in the main tube leading to the intestine, called the common bile duct. Treatment may involve an endoscopic procedure (endoscopic retrograde cholangiopancreatography, or ERCP) to remove the stones in the common bile duct before the gallbladder is removed.
In rare cases of chronic cholecystitis, you may also receive medicine that dissolves gallstones over a period of time.