Related Experiment Video
Updated: May 13, 2026
Rat Burn Model to Study Full-Thickness Cutaneous Thermal Burn and Infection
Published on: August 23, 2022
Effects of azithromycin in Pseudomonas aeruginosa burn wound infection
David P Nichols1, Silvia Caceres, Lindsay Caverly
1Pulmonary Medicine Division, Department of Pediatrics, National Jewish Health, Denver, CO 80206, USA. nicholsd@njhealth.org
Background:
Cutaneous thermal injuries (i.e., burns) remain a common form of debilitating trauma, and outcomes are often worsened by wound infection with environmental bacteria, chiefly Pseudomonas aeruginosa.
Materials And Methods:
We tested the effects of early administration of a single dose of azithromycin, with or without subsequent antipseudomonal antibiotics, in a mouse model of standardized thermal injury infected with P aeruginosa via both wound site and systemic infection. We also tested the antimicrobial effects of these antibiotics alone or combined in comparative biofilm and planktonic cultures in vitro.
Results:
In our model, early azithromycin administration significantly reduced wound and systemic infection without altering wound site or circulating neutrophil activity. The antimicrobial effect of azithromycin was additive with ciprofloxacin but significantly reduced the antimicrobial effect of tobramycin. This pattern was reproduced in biofilm cultures and not observed in planktonic cultures of P aeruginosa.
Conclusion:
These data suggest that early administration of azithromycin following burn-related trauma and infection may reduce P aeruginosa infection and potential interactions with other antibiotics should be considered when designing future studies.
Insights
Early azithromycin administration in burn patients may reduce Pseudomonas aeruginosa infections. Azithromycin
Area of Science:
- Infectious Diseases
- Microbiology
- Burn Trauma Research
Background:
- Cutaneous thermal injuries (burns) are common and debilitating.
- Burn wound infections, primarily with Pseudomonas aeruginosa, worsen outcomes.
- Pseudomonas aeruginosa poses a significant threat in burn care.
Purpose of the Study:
- To evaluate the efficacy of early azithromycin administration in a mouse model of burn injury with Pseudomonas aeruginosa infection.
- To investigate the in vitro antimicrobial effects of azithromycin alone and in combination with other antibiotics against Pseudomonas aeruginosa.
Main Methods:
- A standardized thermal injury mouse model infected with Pseudomonas aeruginosa was used.
- Azithromycin was administered early, with or without subsequent antipseudomonal antibiotics.
- In vitro studies assessed antibiotic effects on planktonic and biofilm cultures of Pseudomonas aeruginosa.
Main Results:
- Early azithromycin significantly reduced wound and systemic Pseudomonas aeruginosa infection in mice.
- Azithromycin's effect was additive with ciprofloxacin but antagonistic with tobramycin in vitro.
- These interactions were observed in biofilm cultures but not planktonic cultures.
Conclusions:
- Early azithromycin administration may be beneficial in managing Pseudomonas aeruginosa infections post-burn.
- Potential interactions between azithromycin and other antibiotics require consideration in clinical practice.
- Further research is warranted to optimize antibiotic strategies for burn wound infections.
