Clinical characteristics, antimicrobial resistance and treatment outcomes of multidrug-resistant Escherichia coli infection in dogs and cats at a veterinary teaching hospital in Thailand

This retrospective study investigated the clinical characteristics of multidrug-resistant (MDR) Escherichia coli and its antimicrobial resistance phenotypes and analyzed the treatment outcomes of MDR E. coli infection in dogs and cats. The medical data of dogs and cats diagnosed in 2020 with E. coli infection at a veterinary teaching hospital were analyzed. Of 94 cases, the frequency of MDR E. coli (66%) infection was higher than that of non-MDR E. coli (34%). MDR E. coli was significantly more frequently detected in female dogs than non-MDR E. coli (P < 0.026). The most frequent MDR E. coli isolation sites were the urinary tract in dogs and skin wounds in cats. MDR E. coli isolates from dogs were highly resistant to ampicillin (96.1%), enrofloxacin (80.4%) and tetracycline (78.4%). Resistance to ampicillin (100%), enrofloxacin (90.9%), marbofloxacin (72.7%) and tetracycline (72.7%) occurred frequently in MDR E. coli isolates from cats. Low resistance to amikacin was detected in the MDR E. coli isolates from dogs and cats. The rates of clinical cure and non-clinical cure of the MDR E. coli and non-MDR E. coli cases were not significantly different. The duration of antimicrobial treatment for MDR E. coli was significantly longer in cats (12.6 ± 5.85 days) than in non-MDR E. coli cases (7 ± 0 days) (P < 0.048). Adjunctive therapy was prescribed more frequently in MDR E. coli (20%) than non-MDR E. coli cases (8.3%). The presence of MDR E. coli was high in this study. High resistance to commonly used antimicrobial drugs and treatment complications was observed in this study.