Antimicrobial options for methicillin-resistant Staphylococcus aureus pyogenic infections: an in vitro comparison of ceftaroline, vancomycin, and linezolid

Abstract Background: The increase in methicillin-resistant Staphylococcus aureus (MRSA)-related pyogenic infections emphasizes the need for new treatment options. Ceftaroline, a fifth-generation cephalosporin, exhibits potent bactericidal activity against MRSA and other Gram-positive pathogens. The Food and Drug Administration approves it for the treatment of complicated skin and skin-structure infections and community-associated pneumonia. This study aims to describe the clinical profile of patients with MRSA pyogenic infections and to assess the susceptibility of these MRSA isolates to ceftaroline and other antimicrobials. Materials and Methods: MRSA isolates from pus samples were identified using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and a cefoxitin antimicrobial disc. The Kirby-Bauer disc diffusion method was used to determine the antimicrobial susceptibility pattern of these MRSA isolates. Ceftaroline susceptibility was assessed with the Kirby-Bauer disc diffusion method, while the E-test determined the minimum inhibitory concentration (MIC). The E-test was also used to determine the MICs of linezolid and vancomycin. Results: The prevalence of MRSA in pus samples was 26.3%. Linezolid showed universal susceptibility (100%), while doxycycline and chloramphenicol demonstrated moderate activity (71.6%). Ceftaroline, tested using the Kirby-Bauer disk diffusion method, showed susceptibility in 95.1% of isolates. All MRSA isolates were susceptible to ceftaroline by E-test. MIC 50 of ceftaroline in MRSA isolates was 0.38 μg/mL, and MIC 90 was 0.5 μg/mL. Susceptibility of MRSA isolates to vancomycin and linezolid was 100% by E-test. The MIC 50 s of vancomycin and linezolid for MRSA isolates were 0.5 and 1 μg/mL, respectively, while the MIC 90 s were 0.75 and 1.5 μg/mL, respectively. Therefore, ceftaroline demonstrates potent in vitro activity against MRSA and could serve as an alternative treatment option. Conclusion: In our study, ceftaroline showed strong in vitro activity against MRSA isolates from pus samples. All MRSA isolates were susceptible to ceftaroline by E-test (100%), and 95.1% were susceptible by the Kirby-Bauer disk diffusion method. Ceftaroline’s excellent in vitro activity, lower MIC values, and favorable safety profile suggest it may serve as a valuable alternative for MRSA pyogenic infections.