Global Prevalence of Antimicrobial Resistance in ESKAPE Pathogens Causing Canine Otitis Externa (1995-2025): A Systematic Review and Meta Analysis

Introduction: Canine otitis externa (COE) remains a clinical challenge due to frequent treatment failures. The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) are major contributors to COE. This study aims to provide a comprehensive global estimate of antimicrobial resistance prevalence across drug classes and to identify resistance trends within these bacterial species.

Methods: Following PRISMA 2020 guidelines, a comprehensive systematic search was conducted across the Scopus, ScienceDirect, PubMed, and ProQuest databases. Ultimately, 37 studies published between 1995 and 2024 comprising 58,223 clinical isolates, met the predefined inclusion criteria. Random-effects model was employed to determine pooled resistance rates for each antimicrobial class using meta package in R software. Heterogeneity was evaluated using the I² statistic.

Results: The pooled prevalence of antimicrobial resistance (AMR) among ESKAPE pathogens in COE was 33.13% (95% CI: 30.80–35.54%). Resistance varied significantly by antibiotic class (p < 0.01), with the highest robust rates observed for beta-lactams (n = 388; 34.36%), aminoglycosides (n = 196; 29.17%), and fluoroquinolones (n = 169; 20.67%). Subgroup analysis by antibiotic type identified highest resistance were observed in second-generation cephalosporins (74.15%), followed by amoxicillin (69.54%) and neomycin (58.58%). At the genus level (p < 0.01), Staphylococcus spp. exhibited significant resistance across multiple antibiotic classes, particularly to beta-lactams (38.82%), and aminoglycosides (32.55%), however Pseudomonas spp. showed very high resistance to amphenicols (91.26%). High heterogeneity (I² > 85%) indicated substantial global variation in AMR patterns.

Conclusion: The escalating resistance of ESKAPE pathogens, particularly against frontline treatments like neomycin and amoxicillin, signals a growing crisis in veterinary dermatology. These findings provide a critical baseline for the development of targeted therapeutic protocols to manage multidrug-resistant infections and to strengthen global antimicrobial stewardship in veterinary field.