Antibiotic resistance in Staphylococcus epidermidis isolates from human and animal skin and soft tissue infections

Staphylococcus epidermidis is a coagulase-negative staphylococcus (CoNS) and an opportunistic pathogen, particularly in patients with compromised immune systems or indwelling medical devices. This study aimed to isolate, identify, and characterize S. epidermidis from human and animal pus samples, assessing its antibiotic resistance profiles. Out of total 250 pus samples, comprising 200 human and 50 animal samples, the prevalence of S. epidermidis was 10% (N=20) in human samples and 34% (N=17) in animal samples, yielding an overall prevalence of 14.08%. The presence of the mecA gene, responsible for methicillin resistance, was detected in 43% of isolates, and the fnbA gene, associated with biofilm formation, was found in 22% of the isolates. Antibiotic susceptibility testing against 59 antimicrobial drugs revealed a high prevalence of resistance to β-lactam antibiotics, particularly cefuroxime (90% in humans, 82.35% in animals), cefmetazole (80% in humans, 88.24% in animals), cephalothin (75% in humans, 88.24% in animals), cefprozil (85% in humans, 76.47% in animals), and cefonicid (75% in humans, 88.24% in animals). Significant resistance was also observed against methicillin and oxacillin, with resistance rates of 60% and 50% in humans, and 52.94% and 70.59% in animals, respectively. Aminoglycosides, such as gentamycin and tobramycin, exhibited moderate resistance, particularly in human isolates. In contrast, vancomycin showed strong activity against both human (75%) and animal (82.35%) isolates, highlighting its effectiveness for treating S. epidermidis infections. Sparfloxacin and levofloxacin, among the fluoroquinolones, demonstrated better efficacy, with high susceptibility observed, particularly in humans. Macrolides, especially azithromycin and erythromycin, showed poor activity, with high resistance observed in both, 90% and 55% in human isolates and 58.82% and 41.18% among animal isolates, respectively. These findings underscore the growing concern of antimicrobial resistance in S. epidermidis , especially in β-lactam, macrolides and aminoglycoside classes, and emphasize the need for careful antibiotic selection, with vancomycin and levofloxacin being promising options for treatment. These findings underscore the growing concern of multidrug-resistant S. epidermidis , particularly in clinical and veterinary settings and highlight the need of rigorous surveillance and antibiotic stewardship in managing S. epidermidis related infections. • The prevalence of S. epidermidis in human and animal samples were 10% and 34% respectively, with an overall prevalence of 14.08%. • The S. epidermidis isolates showed high resistance to β-lactam and macrolide group of antibiotics and moderate resistance to aminoglycosides. • More than 50% of the isolates were found to be methicillin resistant and 22% isolates showed biofilm formation associated gene (fnbA). • The isolates showed high susceptibility to Sparfloxacin (86.49), Vancomycin (78.38%) and Levofloxacin (75.68%). • The growing multidrug-resistant S. epidermidis , stresses the need for antibiotic stewardship and surveillance in both human and veterinary medicine.