Acute Cholecystitis
Inflammation of the gallbladder, most often from a stone obstructing the cystic duct.
Also known as: acute cholecystitis, cholecystitis, calculous cholecystitis, acalculous cholecystitis
Overview
Acute inflammation of the gallbladder, most commonly caused by cystic duct obstruction by a gallstone (calculous cholecystitis, 90-95%) or, less commonly, in the absence of stones (acalculous cholecystitis, often in critically ill patients).
Epidemiology
Affects ~200,000 patients annually in the US. Female predominance (3:1). Increased risk with age and gallstone prevalence (~10-15% of US adults). Acalculous cholecystitis represents 5-10% of cases and carries higher mortality.
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Risk factors
- Gallstones (4 F's: Female, Fat, Forty, Fertile/Fair)
- Obesity, rapid weight loss, bariatric surgery
- Pregnancy
- Estrogen therapy
- Diabetes (gallbladder hypomotility, emphysematous cholecystitis risk)
- Sickle cell disease (pigment stones from hemolysis)
- Cirrhosis
- Critical illness, TPN, prolonged fasting, mechanical ventilation, burns, trauma — predispose to acalculous cholecystitis
Pathophysiology
Stone impaction in the cystic duct (Hartmann pouch) → gallbladder distension → mucosal injury → secondary bacterial infection (E. coli, Klebsiella, Enterococcus). Progressive ischemia leads to gangrene and perforation if untreated. Acalculous cholecystitis: stasis and ischemia in critical illness drive inflammation without obstruction.
Clinical presentation
Symptoms
- Constant, severe RUQ or epigastric pain lasting >6 h (vs <6 h in biliary colic)
- Radiation to right shoulder or interscapular area
- Nausea and vomiting
- Fever and chills
- Anorexia
Signs / physical exam
- RUQ tenderness with positive Murphy sign (inspiratory arrest on palpation of RUQ during deep inspiration)
- Voluntary guarding
- Tachycardia, low-grade fever
- Palpable distended gallbladder in ~30%
- Mild jaundice in ~10% (Mirizzi syndrome — extrinsic CBD compression by stone in cystic duct)
Classic findings
Postprandial RUQ pain lasting >6 h with fever, leukocytosis, and positive Murphy sign.
Differential diagnosis
- Biliary colic — Episodic RUQ pain that resolves within hours, no fever, normal labs, no wall thickening on US — same pain mechanism without sustained obstruction
- Choledocholithiasis / ascending cholangitis — Jaundice, elevated bilirubin, dilated CBD; Charcot triad if cholangitis
- Acute pancreatitis (gallstone) — Epigastric pain radiating to back, lipase elevated >3× ULN
- Hepatitis (viral, alcoholic) — Markedly elevated AST/ALT, jaundice, systemic symptoms
- Peptic ulcer disease / perforation — Epigastric burning; free air on imaging if perforated
- Right lower lobe pneumonia — Cough, dyspnea, hypoxia; CXR
- Inferior MI — Atypical presentation, especially in diabetics; ECG and troponin
- Fitz-Hugh-Curtis (perihepatitis) — Young woman with RUQ pain and PID; chlamydia/gonorrhea
- Hepatic abscess — Fever, RUQ pain; CT shows fluid collection
Diagnostic workup
Diagnostic criteria
Tokyo Guidelines (TG18): (A) local signs — Murphy sign, RUQ mass/pain/tenderness; (B) systemic signs — fever, leukocytosis, elevated CRP; (C) imaging characteristic of cholecystitis. Definite diagnosis requires 1 from A + 1 from B + imaging.
Labs
- CBC — leukocytosis with left shift
- BMP
- LFTs — mildly elevated AST/ALT and alk phos (~30%); marked elevation suggests choledocholithiasis or cholangitis
- Lipase — exclude pancreatitis
- CRP
- Blood cultures if septic
Imaging
- RUQ ultrasound — first-line; findings: gallstones, gallbladder wall thickening >3 mm, pericholecystic fluid, sonographic Murphy sign, distended gallbladder
- Hepatobiliary iminodiacetic acid (HIDA) scan — most sensitive/specific; non-visualization of gallbladder after 1-4 h confirms cystic duct obstruction; used when ultrasound equivocal
- CT abdomen — when alternative diagnoses considered, complications suspected (perforation, emphysematous cholecystitis), or HIDA unavailable
- MRCP — when choledocholithiasis suspected
- EUS — high-resolution evaluation for CBD stones
Diagnostic algorithm
| TG18 Severity Grade | Criteria | Management |
|---|---|---|
| Grade I (Mild) | No organ dysfunction, mild local inflammation | Early laparoscopic cholecystectomy |
| Grade II (Moderate) | WBC >18,000, palpable mass, duration >72 h, marked local inflammation | Early laparoscopic cholecystectomy at center with expertise |
| Grade III (Severe) | Organ dysfunction (CV, neuro, respiratory, renal, hepatic, hematologic) | Stabilize → percutaneous cholecystostomy or delayed surgery |
Treatment
First-line
- NPO, IV fluids, analgesia (NSAIDs and opioids; morphine traditionally avoided over sphincter of Oddi concerns but clinically used)
- IV antibiotics — piperacillin-tazobactam, ceftriaxone + metronidazole, or ertapenem (broaden for severity)
- Early laparoscopic cholecystectomy — within 72 h preferred; equivalent outcomes to delayed cholecystectomy with shorter total hospitalization (ACDC trial)
- Convert to open if anatomy unclear, severe inflammation, or aberrant biliary anatomy suspected
Second-line / adjunct
- Percutaneous cholecystostomy tube — for poor surgical candidates (severe sepsis, ICU patients, high comorbidity) with planned interval cholecystectomy or definitive drainage
- Endoscopic gallbladder drainage (EUS-guided) — emerging alternative for non-operative candidates
- Delayed cholecystectomy 6-8 weeks if patient unable to undergo early surgery and inflammation has cooled
- Treat acalculous cholecystitis with percutaneous cholecystostomy in critically ill patients
Complications
- Gangrenous cholecystitis
- Gallbladder perforation — localized abscess or biliary peritonitis
- Empyema of the gallbladder
- Emphysematous cholecystitis — gas in gallbladder wall; diabetics; Clostridium perfringens, E. coli; HIGH mortality, requires emergent cholecystectomy or open drainage
- Mirizzi syndrome — cystic duct stone compresses CBD causing obstructive jaundice
- Cholecystoenteric fistula — gallstone ileus (stone erodes into duodenum, lodges at ileocecal valve — Rigler triad: pneumobilia, SBO, ectopic stone)
- Sepsis, multiorgan failure
- Postcholecystectomy syndrome (persistent symptoms post-surgery — sphincter of Oddi dysfunction, retained stones)
PANCE pearls
- Early laparoscopic cholecystectomy (<72 h) is preferred over delayed surgery (CHOCOLATE, ACDC trials).
- Murphy sign: inspiratory arrest during RUQ palpation. Sonographic Murphy sign is more specific than clinical exam.
- HIDA scan is the most accurate test for acute cholecystitis when ultrasound is equivocal — non-filling of the gallbladder at 1-4 h confirms cystic duct obstruction.
- Acalculous cholecystitis: think in critically ill, TPN, mechanically ventilated, post-trauma, burn patients — high mortality; cholecystostomy often first-line.
- Emphysematous cholecystitis: diabetic patients, gas in gallbladder wall on imaging, polymicrobial including Clostridium; surgical emergency.
- Gallstone ileus (Rigler triad): pneumobilia + small bowel obstruction + ectopic gallstone; treat with enterolithotomy ± delayed cholecystectomy.
- Mirizzi syndrome: cystic duct stone compressing CBD; preoperative MRCP critical to avoid bile duct injury.
- Sickle cell patients with pigment stones — perioperative care includes transfusion to Hgb ~10 to reduce sickling.
- Pregnancy: laparoscopic cholecystectomy is safe in 2nd trimester; avoid 1st (teratogenicity) and 3rd (technical difficulty).
References
- Tokyo Guidelines TG18 — Yokoe M et al. Tokyo Guidelines 2018: diagnostic criteria and severity grading of acute cholecystitis. J Hepatobiliary Pancreat Sci 2018;25:41-54
- CHOCOLATE Trial — Loozen CS et al. Laparoscopic cholecystectomy versus percutaneous catheter drainage for acute cholecystitis in high-risk patients (CHOCOLATE). BMJ 2018;363:k3965
- WSES 2020 — Pisano M et al. 2020 WSES guidelines for the detection and management of bile duct injury during cholecystectomy. World J Emerg Surg 2020;15:61
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