Acute cholecystitis is a sudden inflammation of the gallbladder that causes severe abdominal pain.

In 90% of cases, acute cholecystitis is caused by gallstones in the gallbladder, which obstruct the duct leading from the gallbladder to the common bile duct (which drains into the intestine). Severe illness, alcohol abuse and, rarely, tumors of the gallbladder may also cause cholecystitis.

The trapped bile becomes concentrated and causes irritation and pressure build-up in the gallbladder. This can lead to bacterial infection and perforation. Attacks may follow a large or fatty meal.

Gallstones occur more frequently in women than men, and it becomes more common with age in both sexes. Native Americans have a higher incidence of gallstones.

The main symptom is abdominal pain -- particularly after a fatty meal -- that is located on the upper right side of the abdomen. Occasionally, nausea and vomiting or fever may occur.

A doctor's examination of the abdomen by touch (palpation) may reveal tenderness.

Tests that detect the presence of gallstones or inflammation include:

• Abdominal ultrasound
• Abdominal CT scan
• Abdominal x-ray
• Oral cholecystogram
• Gallbladder radionuclide scan
• A CBC shows infection by an elevated white blood cell count.

Although cholecystitis may clear up on its own, surgery to remove the gallbladder (cholecystectomy) is usually needed when inflammation persists or recurs. This operation is performed as soon as possible after the onset of cholecystitis, unless the patient is very ill, or if the inflammation is thought to have been present for many days.

Occasionally, in very ill patients, a tube may be placed through the skin to drain the gallbladder until the patient recovers from the acute illness and is fit to undergo surgery.

Cholecystectomy is usually performed using a laparoscope. In this technique, small (1 cm) incisions are made in the abdomen, and instruments and a fiberoptic camera are passed through.

The operation is performed using these small instruments while the surgeon watches the image on a video monitor. Laparoscopic cholecystectomy results in less pain and shorter hospitalization times than an open operation. If there is a significant amount of inflammation, difficulty defining the anatomy, or if significant bleeding occurs, a laparoscopic operation may be converted to an open operation, performed through a larger incision.

Emergency surgery may be necessary if gangrene (tissue death), perforation, pancreatitis, or inflammation of the common bile duct occurs.

Nonsurgical treatment consists of pain control, antibiotics to eliminate the infection, and a low-fat diet when food is tolerated after the acute attack.

When treated with a cholecystectomy procedure, the outlook is usually very good.

• Empyema (pus in the gallbladder)
• Peritonitis (inflammation of the lining of the abdomen)
• Gangrene (tissue death) of the gallbladder
• Injury to the bile ducts draining the liver (a rare complication of cholecystectomy)

Call your health care provider if severe abdominal pain persists.

Call for an appointment with your health care provider if symptoms of cholecystitis recur after an acute episode.

Removal of the gallbladder and the contained gallstones will prevent further attacks of cholecystitis. Reduce the fat content in the diet if you are prone to attacks of cholecystitis.