Inflammation of the gallbladder

E. coli, Klebsiella, Enterococcus, and Enterobacter are the usual pathogens

DDX: hepatitis, liver mets, pancreatitis, pseudocyst, PUD, pyelonephritis, renal stones, pneumonia, pulmonary embolism, myocardial infarction, pre-eruptive zoster

Rheumatalogic disease association: Polyarteritis nodosa results in vasculitis of cystic duct artery and causes cholecystitis

Obstruction of the cystic duct by a gallstone

Acalculous with sludge (? Ischemic)

Erythromycin hepatotoxicity can present with symptoms mimicking acute cholecystitis; Important to elicit antibiotic history during evaluation

History: nausea/vomiting (>50% patients), fever, steady sever epigastric and RUQ pain usually lasting longer than 4-6 hours

Jaundice may be present

Murphy’s sign: ↑ RUQ pain on inspiration, ± palpable gallbladder

↑ WBC, ± ↑ bilirubin and Aφ, and ± ↑ amylase (even in absence of pancreatitis)

Transaminases (ALT/AST) >500 or Bilirubin >4 mg/dl » choledocholithiasis

RUQ U/S: high sensitivity and specificity for gallstones

HIDA (hepatobiliary iminodiacetic acid scan): most sensitive test for acute cholecystitis