Antimicrobial resistance in coagulase-positive staphylococci isolated from companion animals in Australia: A one year study

Abstract

Methicillin-resistant coagulase-positive staphylococci (CoPS) have become increasingly recognised as opportunistic pathogens that limit therapeutic options in companion animals. The frequency of methicillin resistance amongst clinical isolates on an Australia-wide level is unknown. This study determined antimicrobial susceptibility patterns for CoPS isolated from clinical infections in companion animals (dogs, cats and horses) as part of the first nation-wide survey on antimicrobial resistance in animal pathogens in Australia for a one-year period (January 2013 to January 2014). Clinical Staphylococcus spp. isolates (n = 888) obtained from 22 veterinary diagnostic laboratories were identified by MALDI-TOF mass spectrometry and subjected to antimicrobial susceptibility testing for 16 antimicrobials, representing 12 antimicrobial classes. Potential risk factors associated with methicillin resistance in Staphylococcus pseudintermedius isolates from dogs were analysed based on demographic factors and clinical history, including gender, age, previous antimicrobial treatment, chronic and/or recurrent diseases and site of infections. The most commonly identified CoPS were S. pseudintermedius (70.8%; dogs n = 616, cats n = 13) and S. aureus (13.2%, horses n = 53, dogs n = 47 and cats n = 17). Overall, the frequency of methicillin resistance among S. pseudintermedius (MRSP) and S. aureus (MRSA) was 11.8% and 12.8%, respectively. MRSP isolates were strongly associated with resistance to fluoroquinolones (OR 287; 95%CI 91.2–1144.8) and clindamycin (OR 105.2, 95%CI 48.5–231.9). MRSA isolates from dogs and cats were also more likely to be resistant to fluoroquinolones (OR 5.4, 95%CI 0.6–252.1), whereas MRSA from horses were more likely to be resistant to rifampicin. In multivariate analysis, MRSP-positive status was significantly associated with particular infection sites, including surgical (OR 8.8; 95%CI 3.74–20.7), and skin and soft tissue (OR 3.9; 95%CI 1.97–7.51). S. pseudintermedius isolated from dogs with surgical site infections were three times more likely to be methicillin-resistant if cases had received prior antimicrobial treatment. Whilst the survey results indicate the proportion of CoPS obtained from Australian companion animals that are methicillin-resistant is currently moderate, the identified risk factors suggest that it could rapidly increase without adequate biosecurity and infection control procedures in veterinary practice.

Frequency and antimicrobial susceptibility of Staphylococcus pseudintermedius in dogs with otitis externa

“…pseudintermedius was detected in almost 60% of dogs with otitis externa. This rate is higher than that reported in previous studies (LILENBAUM et al, 2000;HOEKSTRA & PAULTON, 2002;PENNA et al, 2010;SAPUTRA et al, 2017). This variation in results might be due to geographical differences, and clinical conditions (with and/or without otitis), age, and breed of the dogs.…”

Perisuspensory abscessation in eight horses with hindlimb cellulitis

“…) but remains relatively low in horse isolates (Saputra et al . ). Seven of eight horses were discharged from the hospital on an oral course of enrofloxacin, subsequent to the results of culture and sensitivity.…”

Antimicrobial effects of cinnamon essential oil and cinnamaldehyde combined with EDTA against canine otitis externa pathogens

“…Tested pathogens in this study were either obtained from a microbial collection of the national survey of AMR in animal conducted in Australia (Saputra et al . ) or isolates associated with canine otitis externa as used previously (Chan et al . ,).…”