Related Experiment Video
Updated: May 19, 2026
Development and Assessment of Intracellular Infection Models for Staphylococcus aureus
Published on: January 17, 2025
In vitro susceptibility of Staphylococcus aureus and Staphylococcus epidermidis isolated from prosthetic joint
Diana Molina-Manso1, Gema del Prado, Alberto Ortiz-Pérez
1Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, Madrid, Spain.
Abstract:
Prosthetic joint infections (PJI) are severe complications in Orthopedics, with Staphylococcus aureus and Staphylococcus epidermidis being the most commonly isolated pathogens. The variable antimicrobial susceptibility found in these microorganisms, along with the increasing number of methicillin-resistant strains, increases the difficulty of antibiotic selection and makes it necessary to perform individual susceptibility studies to select the optimal antibiotic treatment. The aim of this study was to evaluate the in vitro susceptibility pattern of 35 clinical strains isolated from PJI (17 S. aureus and 18 S. epidermidis) against rifampin, vancomycin, tygecicline, clindamycin, cotrimoxazole, cloxacillin, ciprofloxacin, daptomycin and fosfomycin. In vitro susceptibility assays were performed using the broth microdilution method and agar dilution for fosfomycin. MBC was also determined. Tygecicline and daptomycin showed the highest antimicrobial activity with low MIC(90) values, and no resistant strains were detected. On the other hand, ciprofloxacin and cloxacillin exhibited a poor antimicrobial effect with a high percentage of nonsusceptible strains in both species. Bactericidal activity rates revealed the bacteriostatic behavior of rifampin, tygecicline, cotrimoxazole, fosfomycin and clindamycin, whereas vancomycin and cloxacillin showed species- and strain-dependent behavior. Daptomycin and ciprofloxacin were observed to be efficient bactericidal agents against the tested strains. According to our data, rifampin, tigecycline, daptomycin and fosfomycin showed high in vitro activity against most staphylococcal strains isolated from the PJIs tested, although daptomycin seems to be the best alternative to vancomycin therapy.
Insights
This study evaluated antibiotic susceptibility for prosthetic joint infections (PJI). Daptomycin and tigecycline showed high activity against Staphylococcus strains, offering promising alternatives for PJI treatment.
Area of Science:
- Orthopedics
- Infectious Diseases
- Microbiology
Background:
- Prosthetic joint infections (PJI) are serious orthopedic complications.
- Staphylococcus aureus and S. epidermidis are common PJI pathogens.
- Antimicrobial resistance complicates antibiotic selection for PJI.
Purpose of the Study:
- To assess the in vitro antimicrobial susceptibility of clinical Staphylococcus strains from PJI.
- To compare the efficacy of nine antibiotics against S. aureus and S. epidermidis.
- To identify optimal antibiotic choices for PJI treatment.
Main Methods:
- Evaluated 35 clinical Staphylococcus strains (17 S. aureus, 18 S. epidermidis) from PJI.
- Used broth microdilution and agar dilution for in vitro susceptibility testing.
- Determined minimum bactericidal concentration (MBC) for key antibiotics.
Main Results:
- Tigecycline and daptomycin demonstrated potent in vitro activity with no detected resistance.
- Ciprofloxacin and cloxacillin showed poor efficacy and high non-susceptibility rates.
- Daptomycin and ciprofloxacin exhibited efficient bactericidal activity.
Conclusions:
- Rifampin, tigecycline, daptomycin, and fosfomycin show high in vitro activity against staphylococcal PJI strains.
- Daptomycin emerges as a strong alternative to vancomycin for PJI therapy.
- Tailored antibiotic susceptibility testing is crucial for effective PJI management.
Related Concept Videos
01:29Staphylococcal Skin Infections
01:25Clinical Significance of Antibiotic Resistance
01:25Mechanism of Antibiotic Resistance in MRSA