Acute Calculous Cholecystitis

Essential Triad

Acute calculous cholecystitis is characterized by:

• Fever
• Right upper quadrant (RUQ) abdominal pain
• Leukocytosis

These features reflect inflammation of the gallbladder, most commonly due to gallstones.

Etiology & Pathogenesis

• Gallbladder stasis is a common underlying factor
• Causes include:
  • Cholelithiasis (most common in children)
  • External compression (mass, lymph nodes)
  • Trauma
  • Structural duct abnormalities (e.g., choledochal cyst)
  • Microlithiasis (often missed without endoscopic ultrasound)

Risk Factors

See Choledocholithiasis section for detailed pediatric risk factors including obesity, hemolytic disease, medications, and genetic syndromes.

Clinical Features

Symptoms

• RUQ or epigastric pain ± radiation to right shoulder
• Nausea, nonbilious vomiting, anorexia
• Fever
• Murphy sign: inspiratory arrest on RUQ palpation

Laboratory Findings

• Leukocytosis with left shift
• Normal to mildly elevated transaminases
• ↑ Amylase (~8% of cases)
• ↑ Direct and total bilirubin
• ↑ GGT, alkaline phosphatase suggest choledocholithiasis

Diagnosis

Ultrasound

• Gallstones (US more sensitive than CT)
• Wall thickening: >3.0–3.5 mm in children
• Pericholecystic fluid
• Sonographic Murphy sign: sensitivity 6%, specificity 88%, PPV 67%
  
• CBD dilation suggests choledocholithiasis: >3.3 mm in children under 13 (>6mm for adults)
  

HIDA Scan - hepatobiliary iminodiacetic acid scan

• IV Technetium-99m iminodiacetic acid (IDA) uptake by liver → bile → gallbladder
• Normal hepatic uptake with ↓ gallbladder filling after 60 min = cholecystitis
• Morphine improves accuracy by increasing sphincter of Oddi pressure
• False positives:
  • Cystic duct obstruction
  • Hyperbilirubinemia (>4.4 mg/dL)
  • Severe liver disease
  • Prior sphincterotomy
  • TPN or prolonged fasting - due to already full gallbladder
    
• Sensitivity 94%, specificity 65–85% (adults)
• Pediatric study: poor correlation with histology

Management

Supportive Care

• NPO, IV fluids (aggressive in sickle cell disease)
• Analgesia: Ketorolac, morphine (safe)
• Antibiotics:(no clear evidence to support use) - cover enteric flora
  
  • Cefoxitin or piperacillin/tazobactam
  • Recurrence with antibiotics alone: 2.5–22% (better when paired with surgial intervention)
    
  • Post-op antibiotics: no benefit beyond 24 hours

Interventions

• Percutaneous cholecystostomy tube for critically ill patients
• Cholecystectomy:
  • Laparoscopic preferred
  • Timing:
    • Too sick → percutaneous cholecystostomy
    • Deterioration after 24 hrs → surgery
    • Stable → surgery within 1–5 days
    • Sickle cell: transfusion + aggressive IV fluids before surgery
  • Complications: gangrene, rare perforation, pancreatitis
• Choledocholithiasis:
  • Confirm with US
  • ERCP with stone removal before surgery - lowers risk of retained CBD stone
    
  • MRCP useful for ductal stones (common duct)