What is the recommended antibiotic regimen for acute cholecystitis?

From the Guidelines

For acute cholecystitis, the recommended antibiotic regimen typically includes a third-generation cephalosporin (such as ceftriaxone 1-2g IV every 24 hours) plus metronidazole (500mg IV every 8 hours), or alternatively, piperacillin-tazobactam (3.375g IV every 6 hours) or a fluoroquinolone (such as ciprofloxacin 400mg IV every 12 hours) plus metronidazole, as supported by the most recent guidelines 1. The choice of antibiotic regimen depends on the severity of the infection and the patient's risk factors, such as healthcare-associated infections or recent antibiotic exposure.

• For community-acquired acute cholecystitis of mild-to-moderate severity, cefazolin, cefuroxime, or ceftriaxone are recommended 1.
• For community-acquired acute cholecystitis of severe physiologic disturbance, advanced age, or immunocompromised state, imipenem-cilastatin, meropenem, doripenem, piperacillin-tazobactam, ciprofloxacin, levofloxacin, or cefepime, each in combination with metronidazole, are recommended 1.
• For healthcare-associated biliary infections, broader coverage may be needed with carbapenems (such as meropenem 1g IV every 8 hours) or other broad-spectrum agents, as supported by recent guidelines 1. Treatment duration should be 4-7 days, though this may be shortened if the gallbladder is removed or extended if complications like perforation occur.
• Antibiotic selection should cover gram-negative enteric bacteria and anaerobes, as these are the most common pathogens in biliary infections.
• Antibiotics should be adjusted based on culture results when available, as emphasized in recent guidelines 1. While antibiotics are important, definitive treatment typically involves cholecystectomy, with antibiotics serving to control infection before surgery or as the primary treatment in patients who cannot undergo surgery.

From the FDA Drug Label

INTRA-ABDOMINAL INFECTIONS Caused by Escherichia coli, Klebsiella pneumoniae, Bacteroides fragilis, Clostridium species (Note: most strains of Clostridium difficile are resistant) or Peptostreptococcus species. SURGICAL PROPHYLAXIS The preoperative administration of a single 1 gram dose of Ceftriaxone for Injection may reduce the incidence of postoperative infections in patients undergoing surgical procedures classified as contaminated or potentially contaminated (e.g., vaginal or abdominal hysterectomy or cholecystectomy for chronic calculous cholecystitis in high-risk patients, such as those over 70 years of age, with acute cholecystitis not requiring therapeutic antimicrobials, obstructive jaundice or common duct bile stones)

The recommended antibiotic regimen for acute cholecystitis includes Ceftriaxone. Key points to consider:

• Intra-abdominal infections: Ceftriaxone is effective against Escherichia coli, Klebsiella pneumoniae, Bacteroides fragilis, and other organisms that may cause acute cholecystitis.
• Surgical prophylaxis: A single 1 gram dose of Ceftriaxone may reduce the incidence of postoperative infections in patients undergoing cholecystectomy for acute cholecystitis 2.

From the Research

Antibiotic Regimens for Acute Cholecystitis

The recommended antibiotic regimen for acute cholecystitis depends on several factors, including the severity of the clinical manifestations, the onset of the infection, and the penetration of the drug into the bile 3.

Commonly Isolated Microorganisms

The most frequently isolated microorganisms in acute cholecystitis are:

• Escherichia coli
• Klebsiella spp.
• Streptococcus spp.
• Enterococcus spp.
• Clostridium spp. 3, 4

Empirical Antibiotic Therapy

Empirical antibiotic therapy is crucial in preventing surgical complications and limiting the systemic inflammatory response, especially in patients with moderate to severe cholecystitis 3.

• Second-generation cephalosporin (cefotetan) is effective against Gram-negative microorganisms 4
• Vancomycin and teicoplanin are effective against Enterococcus 4
• First-generation cephalosporins may be used for mild-to-moderate acute cholecystitis without gallbladder perforation 5

Antibiotic Selection

The choice of antibiotic should be based on factors such as:

• Severity of clinical manifestations
• Onset of infection (hospital-acquired or community-acquired)
• Penetration of the drug into the bile
• Drug resistance 3
• Periodic antibiotic susceptibility tests should be conducted to select appropriate empirical antibiotics 4

Bile Culture and Antibiotic Susceptibility

Bile cultures and antibiotic susceptibility tests are essential in guiding antibiotic therapy, especially in cases of severe cholecystitis 3, 4.

• Antibiotic stewardship is crucial in the management of bile-related infections 3