Empiric antibiotics for intra-abdominal infections
Overview
Complicated intra-abdominal infections are problems in clinical practice and consume substantial hospital resources. New guidelines will clarify appropriate antibiotics for empiric treatment of complicated intra-abdominal infections...
Management
Community-acquired infections
For appendicitis and other mild to moderate community infections use a single agent such as cefoxitin (Primafoxin, Plucefox) or ticarcillin/clavulanate (Timentin), OR combo therapy such as metronidazole plus cefazolin or ceftriaxone (Rocephin). Reserve tigecycline (Tygacil) because of its broader spectrum and ertapenem (Invanz) to reduce the risk of carbapenem resistance. Avoid ampicillin/sulbactam (Unasyn) due to E. coli resistance, and cefotetan and clindamycin due to increasing B. fragilis resistance, "see table 1".
Table (1). Empiric antibiotic regimens for community-acquired intra-abdominal infections in adults | |
---|---|
Low-risk community-acquired intra-abdominal infections | |
ANTIBIOTIC | DOSE |
Single-agent regimen | |
Piperacillin-tazobactam | 4.5 g IV every 6 hours |
Combination regimen with metronidazole | |
One of the following... | |
Cefazolin | 1 to 2 g IV every 8 hours |
or | |
Cefuroxime | 1.5 g IV every 8 hours |
or | |
Ceftriaxone | 2 g IV once daily |
or | |
Cefotaxime | 2 g IV every 8 hours |
or | |
Ciprofloxacin | 400 mg IV every 12 hours or500 mg PO every 12 hours |
or | |
Levofloxacin | 750 mg IV or PO once daily |
Plus | |
Metronidazole | 500 mg IV or PO every 8 hours |
NOTE:
|
|
High-risk community-acquired intra-abdominal infections in adults | |
ANTIBIOTIC | DOSE |
Single-agent regimen | |
Imipenem-cilastatin | 500 mg IV every 6 hours |
Meropenem | 1 g IV every 8 hours |
Doripenem | 500 mg IV every 8 hours |
Piperacillin-tazobactam | 4.5 g IV every 6 hours |
Combination regimen with metronidazole | |
ONE of the following... | |
Cefepime | 2 g IV every 8 hours |
OR | |
Ceftazidime | 2 g IV every 8 hours |
PLUS | |
Metronidazole | 500 mg IV or PO every 8 hours |
Health care-associated infections
Rely on local susceptibility patterns and use multi-drug regimens if needed. For expanded coverage of gram-negative and facultative bacilli, use agents such as meropenem (Meronem), imipenem/cilastatin (Tienam), doripenem (Doribax), or metronidazole plus cefepime, "see table 2".
- Enterococcal infections
- Treat empirically for enterococci if patients have a SEVERE community-acquired infection or a health care-associated infection especially after surgery. Also cover enterococci empirically in elderly, immunocompromised, or other high-risk adults.
- Use ampicillin, piperacillin/tazobactam (Zosyn), or vancomycin to cover E. faecalis.
- Don't empirically treat for vancomycin-resistant enterococcus (VRE) except for patients at very high risk.
- Methicillin-resistant Staph aureus (MRSA)
- Use vancomycin for health care-associated infections in patients colonized with MRSA or at risk due to treatment failures or prior antibiotic exposure.
- GET OUR NOTE, "The optimal treatment for MRSA bacteremia in adults".
Finally, limit antibiotics to 4 to 7 days if the infection source is eliminated. Longer durations don't improve outcomes. When possible, switch to oral drugs such as moxifloxacin (Avelox), amoxicillin/clavulanate (Augmentin, etc) or metronidazole PLUS ciprofloxacin (Ciprobay), levofloxacin (Tavanic), or an oral cephalosporin.
Table (2). Empiric antibiotic regimens for health care-associated intra-abdominal infections in adults | |
---|---|
ANTIBIOTIC | DOSE |
Single-agent regimen | |
Imipenem-cilastatin | 500 mg IV every 6 hours |
Meropenem | 1 g IV every 8 hours |
Doripenem | 500 mg IV every 8 hours |
Piperacillin-tazobactam | 4.5 g IV every 6 hours |
Combination regimen | |
ONE of the following... | |
Cefepime | 2 g IV every 8 hours |
OR | |
Ceftazidime | 2 g IV every 8 hours |
PLUS | |
Metronidazole | 500 mg IV or PO every 8 hours |
PLUS ONE of the following (in some cases, SEE NOTE BELOW)... | |
Ampicillin | 2 g IV every 4 hours |
OR | |
Vancomycin | 15 to 20 mg/kg IV every 8 to 12 hours |
NOTE:
|
References
- Gelot S, Nakhla E (2016). Intra-abdominal Infections in Adults. US Pharm. 2016;41(4):HS5-HS12.
- Solomkin JS, Mazuski JE, Bradley JS, et al. Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America. Clin Infect Dis. 2010 Jan 15;50(2):133-64.
- Montravers P, Lepape A, Dubreuil L, et al. Clinical and microbiological profiles of community-acquired and nosocomial intra-abdominal infections: results of the French prospective, observational EBIIA study. J Antimicrob Chemother. 2009 Apr;63(4):785-94.
- Solomkin JS, Mazuski JE, Baron EJ, et al. Guidelines for the selection of anti-infective agents for complicated intra-abdominal infections. Clin Infect Dis. 2003 Oct 15;37(8):997-1005.