Antimicrobial Susceptibility Results and Characterization of Skin and Soft Tissue Infections Caused by Staphylococcus aureus in Children

Introduction: Staphylococcus aureus is a major cause of skin and soft tissue infections (SSTIs). This study aimed to determine the antimicrobial susceptibility and clinical and epidemiological characteristics of community-acquired SSTIs caused by methicillin-susceptible and methicillin-resistant S. aureus (MSSA-MRSA) in children. Materials and Methods: This was a retrospective, single-center study of pediatric SSTIs caused by S. aureus at a tertiary care hospital Results: Demographic, clinical, and microbiological data of 431 patients were examined during the study period. Overall, 333 (77.3%) isolates were MSSA, and 98 (22.7%) were MRSA. Antibiotic courses and hospital stays were significantly longer in patients with MRSA infection. The antimicrobial susceptibility patterns for 17 antibiotics were assessed in both MSSA and MRSA isolates. Penicillin resistance rate was 91%, while fosfomycin, gentamicin, mupirocin, trimethoprim-sulfamethoxazole, and fusidic acid resistance rates were 1.2%, 3.2%, 2.7%, 4.2%, and 8.1%, respectively. All S. aureus isolates were susceptible to teicoplanin, vancomycin, linezolid, and tigecycline, and 335 (77%) isolates showed susceptibility to daptomycin. A statistically significant increase was detected in resistance of MSSA isolates to trimethoprim-sulfamethoxazole in 2019 compared to 2014, 2015, 2016 and 2018 (p1= 0.029 (2014 vs. 2019); p2= 0.008 Conclusion: S. aureus strains causing SSTIs showed a continued high prevalence of MSSA and multi-drug susceptibility. A striking result was the detection of increased resistance to trimethoprim-sulfamethoxazole, which was frequently used in oral therapy against MSSA strains in 2019 compared to the other years. These results may provide guidance for clinical management of SSTIs in children.