An investigation of Staphylococcus pseudintermedius isolated from dogs with superficial pyoderma and from their owners

• Main Authors: Yu-Chan Ma, 馬鈺展
• Other Authors: Cheng-Hung Lai
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/7w7853

碩士 === 國立中興大學 === 獸醫學系暨研究所 === 106 === The skin microbiota of dogs includes several species of bacteria, which contributes to the skin defense mechanism. Staphylococcus pseudintermedius plays the role of an opportunistic pathogen, which is cultured at high frequency from the skin of dogs with superficial pyoderma, and effective treatment against infections caused by this pathogen is important in veterinary medicine. Although antibiotic is the standard medication when dealing with bacterial infection, multiple antibiotic-resistant mechanisms gradually developed by bacteria make treatment more challenging nowadays. If S. pseudintermedius was transferred from dogs to humans, it may not only cause direct infection but also exchange drug-resistant gene with other staphylococci on humans. The objective of this survey has three parts. First, we investigate the bacterial species that cause canine superficial pyoderma, the antibiotic-resistant characteristics, drug-resistant genes of isolated S. pseudintermedius, the possible risk factors lead to MRSP infection, and we also compare previous findings with outcomes this time. Second, we investigate the detection rate of S. pseudintermedius from the dog owners and evaluate possible risk factors causing S. pseudintermedius colonizing owners by information from the questionnaire. Third, we find out prevalent dru types of MRSP in Taiwan. Samples were obtained at the National Chung Hsing University from Jun. 2017 to Jan. 2018, and 60 pairs of dogs and owners were included. Sixty-five bacteria were isolated from the dogs, which included 47 S. pseudintermedius (72.3%), 12 other staphylococci (18.5%), 4 other Gram-positive bacteria (6.2%) and 2 Gram-negative bacteria (3.1%). The positive rates of possessing mecA and blaZ of S. pseudintermedius were 34.04% and 80.85%, respectively. More mecA- or blaZ-positive isolates showed resistance against most tested antibiotics and had multiple-drug resistance compared with mecA- or blaZ-negative ones. Dogs which received antimicrobial treatment within a recent month were at significantly higher risk of MRSP infections compared with those which didn’t (p ＜0.05). The detection rate of S. pseudintermedius from 60 samples of owners was 8.33%, and there were no significant risk factors that associated with S. pseudintermedius colonizing owners could be found in this survey. Each MRSP isolate belonged to one of the following three dru types: dt11y (29.41%), dt11a (47.06%) and dt10cp (23.53%). In conclusion, the major pathogen of canine superficial pyoderma is found to be S. pseudintermedius in Taiwan, and isolates which are mecA- or blaZ-positive are generally more resistant to commonly used antibiotics. Compared with the outcomes of previous investigation, we found that S. pseudintermedius isolated from samples of canine superficial pyoderma are apparently more resistant to doxycycline, augmentin, cephalexin, and cephazolin after few years. Although S. pseudintermedius isolated from the owners might be transferred from their dogs, definite risk factors should be further examined in the future study.