Empiric Therapy Regimens

Empiric antibiotic regimens for cholecystitis are outlined below, divided by those for community-acquired acute cholecystitis as categorized by severity of illness, and healthcare–associated cholecystitis of any severity.^{[1, 2, 3, 4, 5]}Consideration of local antibiograms is highly suggested, where available.

Community-acquired acute cholecystitis

Disease of mild-to-moderate severity

Mild severity: Healthy patient, no organ dysfunction, mild inflammatory changes of the gallbladder

Moderate severity: White blood cell (WBC) count above 18,000 cells/mm³, duration of symptoms longer than 72 hours, palpable tender mass in the right upper quadrant, marked local inflammation on imaging studies

Cefazolin 1-2 g IV q8h or
Cefuroxime 1.5 g IV q8h or
Ceftriaxone 1-2 g IV daily

Disease of high severity*

High severity: Patients with organ dysfunction or immunocompromised state

Imipenem-cilastatin 500 mg IV q6h or
Ertapenem 1 g IV q24h or
Meropenem 1 g IV q8h or
Doripenem 500 mg IV q8h or
Piperacillin-tazobactam 3.375 g IV q6h or
Cefepime 2 g IV q8-12h plus metronidazole 500 mg IV q8h or
Ciprofloxacin** 400 mg IV q12h plus metronidazole 500 mg IV q8h or
Levofloxacin** 750 mg IV q24h plus metronidazole 500 mg IV q8h or

*Consider the addition of vancomycin 15-20 mg/kg IV q12h to the above regimens for enterococcal coverage.

**Due to the increasing resistance of E coli to fluoroquinolones, local susceptibility profiles should be reviewed before empiric use.

Healthcare–associated biliary infection of any severity

Pseudomonal and enterococcal coverage is recommended. Recommended regimens include:

Imipenem-cilastatin 250-500 mg IV q6-8h plus vancomycin 15-20 mg/kg IV q12h or
Ertapenem 1 g IV daily plus vancomycin 15-20 mg/kg IV q12h or
Meropenem 0.5-1 g IV q8h plus vancomycin 15-20 mg/kg IV q12h or
Doripenem 500 mg IV q8h plus vancomycin 15-20 mg/kg IV q12h or
Piperacillin-tazobactam 3.375 g IV q6h plus vancomycin 15-20 mg/kg IV q12h or
Cefepime 2 g IV q8-12h plus metronidazole 500 mg IV q8h plus vancomycin 15-20 mg/kg IV q12h or
Ciprofloxacin** 400 mg IV q12h plus metronidazole 500 mg IV q8h plus vancomycin 15-20 mg/kg IV q12h or
Levofloxacin** 750 mg IV daily plus metronidazole 500 mg IV q8h plus vancomycin 15-20 mg/kg IV q12h

**Due to the increasing resistance of E coli to fluoroquinolones, local susceptibility profiles should be reviewed before empiric use.

Duration of therapy

The duration of empiric cholecystitis antibiotic therapy should be guided by severity and clinical improvement, as follows:

For mild cholecystitis, antibiotic therapy should be discontinued within 24 hours of cholecystectomy, unless there is evidence of infection extending outside of the gallbladder.
For moderate-severe cholecystitis, antibiotics should generally be limited to 4-7 days once the source of infection is controlled. Consider 14 days of antibiotics in cases of bacteremia with gram-positive bacteria known to cause infective endocarditis (eg, Enterococcus spp and Streptococcus spp)