What is acute cholecystitis?

What is Acute Cholecystitis?

Acute cholecystitis is an acute inflammatory condition of the gallbladder, most commonly (90-95% of cases) caused by gallstone obstruction of the cystic duct, presenting with right upper quadrant pain, fever, and leukocytosis. 1, 2

Epidemiology and Pathophysiology

• Acute cholecystitis develops in 1-3% of patients with symptomatic gallstones 1
• Approximately 200,000 cases are diagnosed annually in the United States 2
• Calculous cholecystitis (with gallstones) accounts for 90-95% of cases, while acalculous cholecystitis (without gallstones) represents 5-10% and typically occurs in critically ill patients 2, 3
• The mortality rate is approximately 3% overall but increases significantly with age and comorbidities 4

Clinical Presentation

The classic triad consists of: 1

• Right upper quadrant pain (often postprandial)
• Fever
• Leukocytosis

Physical examination typically reveals right upper quadrant tenderness with a positive Murphy's sign 1

Diagnostic Approach

Ultrasound is the first-line imaging modality of choice with sensitivity of approximately 81% and specificity of 83% 1, 2

Key ultrasound findings include: 1

• Pericholecystic fluid (fluid around the gallbladder)
• Distended gallbladder
• Edematous/thickened gallbladder wall (≥3.5 mm)
• Gallstones
• Sonographic Murphy's sign

When ultrasound is non-diagnostic, hepatobiliary scintigraphy (HIDA scan) is the gold standard confirmatory test 2

Treatment Strategy

Standard Management for Surgical Candidates

Early laparoscopic cholecystectomy (ELC) within 7 days of symptom onset—ideally within 72 hours of diagnosis—is the definitive treatment and standard of care 1, 5, 6, 7, 2

Benefits of early surgery include: 1

• Shorter recovery time and hospitalization
• Lower hospital costs
• Fewer work days lost
• Greater patient satisfaction
• Reduced risk of recurrent symptoms and complications

Uncomplicated vs Complicated Disease

For uncomplicated acute cholecystitis in Class A or B patients (low-risk surgical candidates): 1

• Perform urgent cholecystectomy
• No postoperative antibiotics are necessary if source control is complete 1

For complicated acute cholecystitis (gangrenous, perforated, or with abscess): 1

• Class A or B patients: urgent cholecystectomy with short-course postoperative antibiotics (1-4 days)
• Class C patients (high-risk): emergent cholecystectomy with postoperative antibiotic therapy

Special Populations

Elderly patients (>65 years): 1, 2

• Early laparoscopic cholecystectomy should still be performed when feasible
• Surgery within 10 days of symptom onset is safe, though earlier is better
• Laparoscopic cholecystectomy is associated with lower 2-year mortality (15.2%) compared with nonoperative management (29.3%) 2

Pregnant patients: 2

• Early laparoscopic cholecystectomy is recommended during all trimesters
• Associated with lower maternal-fetal complications (1.6% for early vs 18.4% for delayed)

Transplanted or immunocompromised patients: 1

• Laparoscopic cholecystectomy should be performed as soon as possible after diagnosis
• These patients have higher severity and mortality risk

Alternative Management for High-Risk Patients

Percutaneous cholecystostomy is indicated for: 1

• Critically ill patients with multiple comorbidities unfit for surgery (ASA III/IV)
• Patients with septic shock or severe hemodynamic instability
• Patients who fail to improve after 3-5 days of antibiotic therapy

Important caveats about cholecystostomy: 1, 2

• Should be considered a bridge to surgery rather than definitive treatment in most cases
• Associated with higher postprocedural complications (65%) compared to laparoscopic cholecystectomy (12%) 2
• Clinical resolution typically occurs within 24-48 hours in 92% of patients 1
• Conservative treatment (antibiotics alone or with drainage) leads to frequent recurrence and should not be considered definitive therapy 8

Gallbladder Perforation

Early diagnosis and immediate surgical intervention are critical as perforation occurs in 2-11% of acute cholecystitis cases with mortality rates of 12-16% 1

Three types of perforation: 1

• Type I (acute/free): generalized peritonitis requiring emergency surgery
• Type II (subacute): pericholecystic abscess with localized peritonitis
• Type III (chronic): cholecystoenteric fistula

Antibiotic Therapy

Empirical broad-spectrum antibiotics should be initiated promptly: 5, 6

• Non-critical patients: amoxicillin/clavulanate 6
• Critically ill patients: piperacillin-tazobactam 5, 6
• Duration depends on disease severity and source control adequacy 1

Common Pitfalls to Avoid

• Do not delay surgery beyond 7-10 days from symptom onset as inflammation becomes more difficult to manage and conversion rates increase 1, 7
• Do not routinely use delayed cholecystectomy (6-12 weeks later) as this approach results in higher recurrence rates, longer total hospitalization, and increased complications 1
• Do not rely solely on conservative management as 76% of patients eventually require cholecystectomy, with 36% experiencing readmission 8
• Do not overlook acalculous cholecystitis in critically ill patients as it carries high mortality if diagnosis is delayed 3