Otitis externa in cats is a common external ear canal inflammation. Usually caused by parasites and subsequent bacterial infections. In this study Otodectes cynotis (O. cynotis) infestation was examined. In addition, bacterial pathogens and antimicrobial resistance (AMR) patterns and multiple antibiotic resistance indices (MARI) of Staphylococcus isolates from cats with otitis externa from Northern Palestine were also examined. AMR in companion animal bacterial infections raises therapeutic and public health problems.
Ear samples were taken from 40 cats with otitis externa, from which O. cynotis was detected. Bacterial isolates were identified using standard microbiological methods. Antimicrobial susceptibility testing against 22 antimicrobial agents using disk diffusion test was performed. MARI was estimated for Staphylococcus isolates.
In total, 80% (32/40) of the examined cats were infested with O. cynotis. Most of the 42 bacterial isolates were Staphylococcus aureus (S. aureus) (71.4%, 30/42), followed by coagulase-negative Staphylococci (CoNS) (23.8%, 10/42) and Pseudomonas aeruginosa (P. aeruginosa) (4.8%, 2/42). Mixed S. aureus and P. aeruginosa infections was 5% (2/40). All Staphylococcus isolates were multidrug-resistant. S. aureus isolates had a mean MARI of 0.706 ± 0.128 (range: 0.45-0.95), while CoNS isolates had 0.674 ± 0.088 (range: 0.59-0.82). All isolates were penicillin- and ampicillin-resistant. S. aureus and CoNS MARI values were not significantly different (U = 178.0, p = 0.292). Neither host breed nor sex had a significant effect on bacterial isolation rates.
Due to O. cynotis' high incidence and multidrug resistance, parasitological diagnosis and antibiotic susceptibility testing are necessary in cats with otitis externa. The limited sample size and the fact that cats were sourced from a single veterinary clinic should be viewed with caution. Cat otitis externa incidence and antibiotic resistance in Northern Palestine need extensive multicenter investigation. Our findings highlight the necessity of antimicrobial stewardship, antibiotic resistance assessments, and parasitological analyzes in Northern Palestine for One Health.

Otitis externa in cats is a common external ear canal inflammation. Usually caused by parasites and subsequent bacterial infections. In this study Otodectes cynotis (O. cynotis) infestation was examined. In addition, bacterial pathogens and antimicrobial resistance (AMR) patterns and multiple antibiotic resistance indices (MARI) of Staphylococcus isolates from cats with otitis externa from Northern Palestine were also examined. AMR in companion animal bacterial infections raises therapeutic and public health problems.
Ear samples were taken from 40 cats with otitis externa, from which O. cynotis was detected. Bacterial isolates were identified using standard microbiological methods. Antimicrobial susceptibility testing against 22 antimicrobial agents using disk diffusion test was performed. MARI was estimated for Staphylococcus isolates.
In total, 80% (32/40) of the examined cats were infested with O. cynotis. Most of the 42 bacterial isolates were Staphylococcus aureus (S. aureus) (71.4%, 30/42), followed by coagulase-negative Staphylococci (CoNS) (23.8%, 10/42) and Pseudomonas aeruginosa (P. aeruginosa) (4.8%, 2/42). Mixed S. aureus and P. aeruginosa infections was 5% (2/40). All Staphylococcus isolates were multidrug-resistant. S. aureus isolates had a mean MARI of 0.706 ± 0.128 (range: 0.45-0.95), while CoNS isolates had 0.674 ± 0.088 (range: 0.59-0.82). All isolates were penicillin- and ampicillin-resistant. S. aureus and CoNS MARI values were not significantly different (U = 178.0, p = 0.292). Neither host breed nor sex had a significant effect on bacterial isolation rates.
Due to O. cynotis' high incidence and multidrug resistance, parasitological diagnosis and antibiotic susceptibility testing are necessary in cats with otitis externa. The limited sample size and the fact that cats were sourced from a single veterinary clinic should be viewed with caution. Cat otitis externa incidence and antibiotic resistance in Northern Palestine need extensive multicenter investigation. Our findings highlight the necessity of antimicrobial stewardship, antibiotic resistance assessments, and parasitological analyzes in Northern Palestine for One Health.