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Biliary Tract Infection

An Antimicrobial Stewardship Program clinical summary.
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These materials are intended for general clinical education and guidance. They are not a substitute for a clinician’s knowledge, skill or judgment in treating patients.

Background

  • Acute cholecystitis is characterized by right upper quadrant pain, fever and leukocytosis, resulting from inflammation of the gallbladder
    • Complicated: Associated with local or systemic complications such as gallbladder gangrene, perforation, empyema, pericholecystic abscess or biliary fistula
    • Uncomplicated: Does not fulfil the criteria for complicated
  • Acute ascending cholangitis is a clinical syndrome characterized by fever, jaundice and abdominal pain that develops as a result of biliary obstruction or stasis. The term “ascending” denotes infection originating from bacteria in the duodenum that ascend into the biliary tree.
  • Severe: Hemodynamic instability and/or evidence of organ dysfunction
  • Non-severe: Does not meet the criteria for severe infection at initial diagnosis
  • Risk of resistance: Risk factors include but are not limited to invasive procedures (such as biliary stenting or drainage) within three months, broad-spectrum antimicrobial use within 30 days
  • Obstructive jaundice secondary to choledocholithiasis or malignancy in the absence of signs of infection (e.g., afebrile, normal WBC, normal CRP) requires only periprocedural (i.e., ERCP) antimicrobial prophylaxis.

Common pathogens

  • Enterobacterales (e.g., E. coli, K. pneumoniae, Proteus spp.)

Empiric therapy

Acuity and risk of resistance

1st line

Alternative for allergy to 1st line*

Non-severe

AND

Low risk of resistance

Ceftriaxone 1 g IV q24h

If presence of biliary-enteric anastomosis, ADD: Metronidazole 500 mg PO/IV q12h

OR

Amoxicillin/clavulanate 875 mg/125 mg PO BID
 

Ciprofloxacin 500 mg PO or 400 mg IV q12h

If presence of biliary-enteric anastomosis, ADD: Metronidazole 500 mg PO/IV q12h
 

Severe

AND/OR

High risk of resistance
 

Piperacillin-tazobactam 4.5 g IV q6h (extended infusion)

If beta-lactam possible: 
Meropenem 1 g IV q8h (extended infusion)

If beta-lactam not possible: 
Ciprofloxacin 400 mg IV q12h AND Tobramycin 7 mg/kg IV q24h × 1 to 2 doses pending culture results

If presence of biliary-enteric anastomosis, ADD: Metronidazole 500 mg PO/IV q12h

*Patients with a history of intolerance, non-specific rash to beta-lactams or type I hypersensitivity to penicillin or amoxicillin can generally receive ceftriaxone safely. Patients with SJS/TEN, DRESS, AGEP or any other severe type II–IV hypersensitivity reaction should avoid ceftriaxone. See Beta-lactam Allergy Assessment and Management clinical summary.

Duration of therapy

  • Cholecystitis, surgical/percutaneous source control:
    • Cholecystectomy, uncomplicated: no post-operative antibiotics
    • Cholecystectomy, complicated: up to 4 days post-operatively
    • Cholecystostomy tube: up to 4 days after tube insertion
  • Cholecystitis, medical management:
    • Uncomplicated: 5 to 7 days
    • Complicated: 7 to 14 days, dependent upon imaging and/or symptom resolution
  • Cholangitis:
    • ERCP/biliary drainage: 3 days after adequate source control (extend to 7 days total if associated bacteremia)
Accordion Items
  1. Gu, Xue-Xiang, et al. "Clinical and microbiological characteristics of patients with biliary disease." World Journal of Gastroenterology 26.14 (2020): 1638.
  2. Pisano, Michele, et al. "2020 World Society of Emergency Surgery updated guidelines for the diagnosis and treatment of acute calculus cholecystitis." World Journal of Emergency Surgery 15 (2020): 1–26.
  3. Wu, Pei-Shan, et al. "Anaerobic coverage as definitive therapy does not affect clinical outcomes in community-onset bacteremic biliary tract infection without anaerobic bacteremia." BMC infectious diseases 18 (2018): 1–7.
  4. Srinu, Deshidi, et al. "Conventional vs short duration of antibiotics in patients with moderate or severe cholangitis: Non-inferiority randomized trial." Official Journal of the American College of Gastroenterology | ACG (2022): 10-14309.