Complications Without treatment, 10% of patients develop localized perforation, and 1% develop free perforation and peritonitis. Increasing abdominal pain, high fever, and rigors with rebound tenderness or ileus suggest empyema (pus) in the gallbladder, gangrene, or perforation. When acute cholecystitis is accompanied by jaundice or cholestasis, partial common duct obstruction is likely, usually due to stones or inflammation. Other complications include the following: Mirizzi syndrome: Rarely, a gallstone becomes impacted in the cystic duct and compresses and obstructs the common bile duct, causing cholestasis. Gallstone pancreatitis: Gallstones pass from the gallbladder into the biliary tract and block the pancreatic duct. Cholecystoenteric fistula: Infrequently, a large stone erodes the gallbladder wall, creating a fistula into the small bowel (or elsewhere in the abdominal cavity); the stone may pass freely or obstruct the small bowel (gallstone ileus).
• Diagnosis
Ultrasonography Cholescintigraphy if ultrasonography results are equivocal or if acalculous cholecystitis is suspected Acute cholecystitis is suspected based on symptoms and signs. Transabdominal ultrasonography is the best test to detect gallstones. The test may also elicit local abdominal tenderness over the gallbladder (ultrasonographic Murphy sign). Pericholecystic fluid or thickening of the gallbladder wall indicates acute inflammation. Cholescintigraphy is useful when results are equivocal; failure of the radionuclide to fill the gallbladder suggests an obstructed cystic duct (ie, an impacted stone). False-positive results may be due to the following: A critical illness Receiving TPN and no oral foods (because gallbladder stasis prevents filling) Severe liver disease (because the liver does not secrete the radionuclide) Previous sphincterotomy (which facilitates exit into the duodenum rather than the gallbladder)