Griffeth Gregory C, Morris Daniel O, Abraham Jill L, Shofer Frances S, Rankin Shelley C
Department of Clinical Studies, University of Pennsylvania School of Veterinary Medicine, Philadelphia, PA, USA.
Vet Dermatol. 2008 Jun;19(3):142-9. doi: 10.1111/j.1365-3164.2008.00663.x.
Methicillin resistance rates of 41% for Staphylococcus aureus, 16% for S. intermedius, and 40% for S. schleiferi have recently been reported in canine patients. These were deemed to be reflective of referral and clinician-selection biases, which would imply significantly lower methicillin-resistant staphylococcal carriage rates in less-biased canine populations. In this study, swabs for bacterial culture were collected from five cutaneous sites on each of 50 healthy dogs and 59 dogs with inflammatory skin disease to determine prevalence of carriage and relative frequency of methicillin resistance in coagulase-positive staphylococci and S. schleiferi ssp. schleiferi. These were identified morphologically and by Gram's staining, catalase and coagulase testing, and biochemical speciation. Coagulase-positive staphylococci and S. schleiferi ssp. schleiferi were isolated from 88% (52 of 59) of affected dogs. Species identified in the culture-positive dogs were: S. aureus in 12%, S. intermedius (92%), S. schleiferi ssp. schleiferi (10%), and S. schleiferi ssp. coagulans (10%) with methicillin resistance rates of 17%, 8%, 20% and 20%, respectively. Coagulase-positive staphylococci were isolated from 74% (37 of 50) of healthy dogs: S. aureus (16%), S. intermedius (92%) and S. schleiferi ssp. coagulans (5%). Methicillin resistance rates were 0%, 3% and 50%, respectively. Of total methicillin-resistant isolates, 11 of 13 were positive for PBP2a via latex agglutination. Methicillin-resistant S. intermedius and S. schleiferi ssp. schleiferi isolates were all positive for the mecA gene via PCR. There was no significant difference in staphylococcal isolation or methicillin resistance between study groups. While present, methicillin-resistant coagulase-positive staphylococci are significantly less common in these less-biased populations than in the clinical isolates previously reported from this institution which provided the impetus for this study.
最近有报道称，犬类患者中金黄色葡萄球菌的耐甲氧西林率为41%，中间葡萄球菌为16%，施氏葡萄球菌为40%。这些被认为反映了转诊和临床医生选择偏倚，这意味着在偏倚较小的犬类群体中，耐甲氧西林葡萄球菌的携带率会显著更低。在本研究中，从50只健康犬和59只患有炎症性皮肤病的犬的每个犬的五个皮肤部位采集用于细菌培养的拭子，以确定凝固酶阳性葡萄球菌和施氏葡萄球菌施氏亚种的携带率和耐甲氧西林的相对频率。通过形态学、革兰氏染色、过氧化氢酶和凝固酶检测以及生化鉴定来识别它们。凝固酶阳性葡萄球菌和施氏葡萄球菌施氏亚种从88%（59只中的52只）的患病犬中分离出来。在培养阳性的犬中鉴定出的菌种为：金黄色葡萄球菌占12%，中间葡萄球菌（92%），施氏葡萄球菌施氏亚种（10%），以及施氏葡萄球菌凝聚亚种（10%），其耐甲氧西林率分别为17%、8%、20%和20%。凝固酶阳性葡萄球菌从74%（50只中的37只）的健康犬中分离出来：金黄色葡萄球菌（16%），中间葡萄球菌（92%）和施氏葡萄球菌凝聚亚种（5%）。耐甲氧西林率分别为0%、3%和50%。在所有耐甲氧西林分离株中，13株中有11株通过乳胶凝集试验检测PBP2a呈阳性。耐甲氧西林的中间葡萄球菌和施氏葡萄球菌施氏亚种分离株通过PCR检测mecA基因均呈阳性。研究组之间在葡萄球菌分离或耐甲氧西林方面没有显著差异。虽然存在耐甲氧西林的凝固酶阳性葡萄球菌，但在这些偏倚较小的群体中，其显著少于此前该机构报告的临床分离株，而正是后者推动了本研究。
