From the Guidelines
Cefdinir is not effective against Pseudomonas aeruginosa. This third-generation cephalosporin antibiotic has good activity against many gram-positive and some gram-negative bacteria, but it lacks reliable activity against Pseudomonas aeruginosa 1. Pseudomonas has intrinsic resistance mechanisms including low outer membrane permeability and efficient efflux pumps that make it naturally resistant to cefdinir.
Key Points to Consider
- The recent guidelines for the treatment of infections due to multidrug-resistant organisms, published in the Journal of Microbiology, Immunology and Infection in 2022 1, do not recommend cefdinir for the treatment of Pseudomonas aeruginosa infections.
- Alternative antibiotics with anti-pseudomonal activity, such as ceftazidime, cefepime, piperacillin-tazobactam, carbapenems, fluoroquinolones like ciprofloxacin, or aminoglycosides, should be used instead.
- The choice of specific anti-pseudomonal agent depends on the infection site, severity, local resistance patterns, and patient factors.
- Empiric therapy for suspected Pseudomonas infections often includes combination therapy until susceptibility results are available.
Treatment Options
- For carbapenem-resistant Pseudomonas aeruginosa (CRPA) and difficult-to-treat P. aeruginosa (DTR-PA), recommended treatment options include piperacillin-tazobactam, ceftazidime, cefepime, and ciprofloxacin 1.
- Colistin monotherapy or combination therapy, ceftolozane/tazobactam, and ceftazidime/avibactam are also recommended for DTR-PA 1.
From the FDA Drug Label
Cefdinir is inactive against most strains of Enterobacter spp., Pseudomonas spp., Enterococcus spp., penicillin-resistant streptococci, and methicillin-resistant staphylococci.
Cefdinir is not effective against Pseudomonas aeruginosa 2.
From the Research
Effectiveness of Cefdinir against Pseudomonas aeruginosa
- Cefdinir is a third-generation cephalosporin with a broad spectrum of antibacterial activity, but its effectiveness against Pseudomonas aeruginosa is limited 3.
- According to the available evidence, cefdinir is not effective against Pseudomonas aeruginosa, and other antibiotics such as ceftazidime, cefiderocol, and ceftolozane-tazobactam have shown better activity against this pathogen 4, 5, 6.
- Ceftazidime is currently the most active cephalosporin available against Pseudomonas aeruginosa, but cefdinir is not recommended as a sole antibiotic therapy for pseudomonal infections 7, 5.
- Newer antibiotics such as cefiderocol, ceftazidime-avibactam, and ceftolozane-tazobactam have shown promising activity against multidrug-resistant Pseudomonas aeruginosa, but cefdinir is not among them 4, 6.
Alternatives to Cefdinir for Pseudomonas aeruginosa Infections
- Ceftazidime, cefiderocol, and ceftolozane-tazobactam are alternative antibiotics that have shown effectiveness against Pseudomonas aeruginosa 4, 5, 6.
- These antibiotics have been studied in various clinical trials and have demonstrated good clinical and bacteriological efficacy against Pseudomonas aeruginosa infections 4, 5, 6.
- However, the emergence of resistance to these antibiotics is a concern, and additional antibiotic development is warranted to provide sufficient options to successfully manage Pseudomonas aeruginosa infections 6.