Overview
Definition
Inflammation of the gallbladder, almost always caused by a gallstone impacting in the cystic duct.
Epidemiology
Very common in Western countries. Risk factors follow the '4 Fs': Female, Fat, Forty, Fertile.
Etiology & Risk Factors
- Gallstones (90-95%): Cholesterol stones or Pigment stones blocking the cystic duct
- Acalculous cholecystitis (5-10%): Seen in critically ill, fasting, or ICU patients due to biliary stasis
Clinical Symptoms
- Severe, steady Right Upper Quadrant (RUQ) or epigastric pain
- Pain may radiate to the right shoulder or scapula (Boas sign)
- Often precipitated by eating a fatty meal
- Fever, nausea, and vomiting
Clinical Approach
Diagnosis
- Physical Exam: Positive Murphy's sign (inspiratory arrest upon deep palpation of the RUQ)
- Labs: Leukocytosis. Bilirubin and AST/ALT are typically NORMAL or mildly elevated (if highly elevated, suspect choledocholithiasis or cholangitis)
- Ultrasound (Initial test of choice): Gallbladder wall thickening (>3mm), pericholecystic fluid, gallstones, sonographic Murphy's sign
- HIDA Scan (Gold Standard if US is equivocal): Non-visualization of the gallbladder indicates cystic duct obstruction
Management
- NPO, IV fluids, IV antibiotics (covering enteric Gram-negatives and anaerobes)
- Pain control (NSAIDs or Opioids)
- Laparoscopic Cholecystectomy (definitively within 48-72 hours of symptom onset)
Complications
- Gallbladder gangrene and perforation
- Gallstone ileus (fistula forms between gallbladder and bowel)
- Mirizzi syndrome (stone in cystic duct compresses the common bile duct)