Acute calculous cholecystitis

Background

• Inflammation of the gallbladder caused by obstruction of the cystic duct by gallstones
• Most common complication of cholelithiasis
• 10-20% of patients with gallstones will develop cholecystitis
• Risk factors (5 F's — mnemonic):
  • Female, Forty, Fertile (multiparity), Fat (obesity), Fair (Northern European descent)
  • Additional: rapid weight loss, TPN, medications (estrogen, fibrates, octreotide)
• Pathophysiology: cystic duct obstruction → gallbladder distension → wall inflammation → secondary infection (in ~50%)
• Complications: gangrenous cholecystitis (20%), perforation (2-15%), gallstone ileus, cholecystoenteric fistula, emphysematous cholecystitis

Clinical Features

• RUQ pain (constant, >4-6 hours duration — distinguishes from biliary colic which resolves)
• Pain radiates to right scapula or shoulder (phrenic nerve irritation)
• Nausea and vomiting (common)
• Fever (low-grade; high fever suggests complications)
• Murphy sign: inspiratory arrest during RUQ palpation (sensitivity ~65%)
  • Sonographic Murphy sign (pain with probe pressure over sonographically visualized gallbladder) is more specific
• RUQ guarding, rebound tenderness (suggests peritonitis)
• Jaundice suggests choledocholithiasis (common bile duct stone) or cholangitis (Charcot triad/Reynolds pentad)

Differential Diagnosis

• Biliary colic (most important to distinguish — resolves within 4-6h)
• Choledocholithiasis / cholangitis
• Hepatitis
• Peptic ulcer disease
• Pancreatitis
• Appendicitis (especially high-riding appendix)
• Pneumonia (RLL)
• Pyelonephritis / nephrolithiasis
• MI (inferior — especially in elderly/diabetics)
• Fitz-Hugh-Curtis syndrome (perihepatitis)

Evaluation

Labs

• WBC: leukocytosis (12,000-15,000); WBC >20,000 suggests gangrenous or emphysematous cholecystitis
• LFTs: mild elevation of AST/ALT; alkaline phosphatase and bilirubin elevated if CBD stone
• Lipase: rule out concurrent pancreatitis (gallstone pancreatitis)
• Lactate: if septic
• Blood cultures: if febrile or septic
• Pregnancy test in reproductive-age women

RUQ Ultrasound (Test of Choice)

• Sensitivity 88%, specificity 80% for acute cholecystitis
• Findings:
  • Gallstones (echogenic foci with posterior acoustic shadowing)
  • Gallbladder wall thickening >3-4 mm (nonspecific — also seen in CHF, ascites, hepatitis)
  • Pericholecystic fluid
  • Sonographic Murphy sign (most predictive single finding)
  • Gallbladder distension (>10 cm long or >5 cm transverse)
• Combined findings increase diagnostic accuracy

HIDA Scan

• Most accurate test for cholecystitis (sensitivity 97%, specificity 90%)
• Non-visualization of gallbladder at 4 hours = positive for cholecystitis (cystic duct obstruction)
• Takes 1-4 hours to complete — not practical for acutely ill ED patients
• Use when US equivocal and diagnosis uncertain

CT

• Not first-line but may show gallbladder distension, wall thickening, pericholecystic stranding
• Useful for identifying complications (perforation, abscess, emphysematous changes)

Management

ED Management

• NPO
• IV fluid resuscitation
• Pain control:
  • Ketorolac 15-30 mg IV (shown to be effective and may reduce gallbladder inflammation)
  • Opioids (morphine or hydromorphone) — traditional concern about sphincter of Oddi spasm is likely overstated
• Antiemetics: ondansetron 4 mg IV
• Antibiotics if complicated (febrile, septic, diabetic, immunocompromised):
  • Piperacillin-tazobactam 3.375-4.5g IV OR
  • Ceftriaxone 2g IV + metronidazole 500 mg IV
  • Coverage: gram-negatives (E. coli, Klebsiella) and anaerobes
• Surgical consultation for cholecystectomy

Definitive Treatment

• Laparoscopic cholecystectomy (standard of care)
• Early cholecystectomy (<72 hours) preferred — associated with shorter hospital stays and lower complication rates
• Percutaneous cholecystostomy for patients too unstable for surgery (critically ill, multiple comorbidities)

Special Populations

• Acalculous cholecystitis: occurs in critically ill/ICU patients without gallstones (5-10% of cases)
• Emphysematous cholecystitis: gas-forming organisms; higher perforation risk; more common in diabetic men
• Elderly/diabetics: higher risk of complications, may present atypically

Disposition

• Admit all patients with acute cholecystitis
• ICU if septic, gangrenous, or emphysematous cholecystitis
• Surgical consultation in ED for early cholecystectomy

See Also

• Biliary colic
• Choledocholithiasis
• Cholangitis
• Gallstone pancreatitis
• Acalculous cholecystitis

References

• Yokoe M, et al. Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis. J Hepatobiliary Pancreat Sci. 2018;25(1):41-54. PMID 29032636
• Ansaloni L, et al. 2016 WSES guidelines on acute calculous cholecystitis. World J Emerg Surg. 2016;11:25. PMID 27307785
• Trowbridge RL, et al. Does this patient have acute cholecystitis? JAMA. 2003;289(1):80-86. PMID 12503981