Susceptibility of Incisional Site Staphylococcus spp. to Three Common Perioperative Antimicrobials in Dogs Undergoing Clean Orthopaedic Procedures

Abstract

Objectives The aim of this study was to evaluate the susceptibility pattern of the incisional site Staphylococcus spp. to three commonly used perioperative antimicrobials in dogs.Materials and Methods A cohort of client-owned dogs was included in this prospective observational study. After induction of general anaesthesia and hair clipping, culture samples were collected from the incisional site of healthy dogs before orthopaedic surgery. The isolated colonies were identified. The susceptibility pattern of staphylococcal isolates was determined using Clinical and Laboratory Standard Institute standards. The staphylococcal susceptibilities to amoxicillin/clavulanic acid and cefpodoxime were compared with cefazolin using two-sided equality of proportions test.Results A total of 391 bacterial isolates were identified in 115 dogs. Bacillus spp. (n = 200) and Staphylococcus spp. (n = 95) were the most common bacteria isolated. Coagulase- positive and -negative staphylococci were isolated in 44 and 38% of dogs respectively. Cefazolin, amoxicillin/clavulanic acid and cefpodoxime staphylococcal susceptibilities were 68, 77 and 76% respectively. There were no significant differences in Staphylococcus spp. susceptibility between amoxicillin/clavulanic acid or cefpodoxime and cefazolin (p = 0.19, p = 0.25). Thirty-six per cent of coagulase-negative staphylococci and 6% of coagulase-positive staphylococci isolated were methicillin resistant.Conclusion Cefazolin, amoxicillin/clavulanic acid and cefpodoxime had similar susceptibilities for staphylococcal isolates. Routine use of amoxicillin/clavulanic acid or cefpodoxime in replace of cefazolin should be practiced with caution.