Boynosky Nicole Ann, Stokking Laura B
From the Dermatology Department, Veterinary Specialty Hospital, San Diego, CA.
J Am Anim Hosp Assoc. 2015 Nov-Dec;51(6):372-9. doi: 10.5326/JAAHA-MS-6243.
Corynebacterium species are considered nonpathogenic in canine dermatitis; however, potential clinical significance has been demonstrated in canine otitis externa and from a dog bite wound in a human. Objectives of this study were to identify the predominant Corynebacterium species present in lesions of canine dermatitis, assess pathogenic role, determine antimicrobial susceptibility, and evaluate clinical response. Of 37 isolates identified as Corynebacterium, 31 were Corynebacterium auriscanis . Most Corynebacterium isolates were susceptible to chloramphenicol (97%), tetracyclines (92%), and amikacin (89%); isolate susceptibilities to β-lactams, trimethoprim-sulfonamides, and fluoroquinolones were <50%. Most cultures grew mixed populations of bacteria; C. auriscanis was the only organism isolated in three patients. At recheck, 2-8 wk after initial presentation, pleomorphic rods were absent or significantly decreased in all patients. Two of three C. auriscanis isolates were obtained in pure culture and were evaluable, meaning patient had an initial exam and recheck examination. Both patients were already on antimicrobials to which C. auriscanis was resistant in vitro. Both improved after doxycycline administration. C. auriscanis may act as an opportunistic pathogen in canine dermatitis and may not respond to antimicrobial therapy based on susceptibilities for other organisms in mixed infections. Occasionally, Corynebacterium isolated alone may be pathogenic.
棒状杆菌属被认为在犬类皮炎中无致病性；然而，其在犬类外耳炎以及人类的犬咬伤伤口中已显示出潜在的临床意义。本研究的目的是鉴定犬类皮炎病变中存在的主要棒状杆菌属物种，评估其致病作用，确定抗菌药敏性，并评估临床反应。在37株被鉴定为棒状杆菌属的菌株中，31株为耳道棒状杆菌。大多数棒状杆菌属菌株对氯霉素（97%）、四环素（92%）和阿米卡星（89%）敏感；对β-内酰胺类、甲氧苄啶-磺胺类和氟喹诺酮类的菌株敏感性<50%。大多数培养物生长出混合菌群；耳道棒状杆菌是三名患者中唯一分离出的微生物。在初次就诊后2 - 8周复查时，所有患者中多形性杆菌消失或显著减少。在纯培养中获得并可评估的三株耳道棒状杆菌中有两株，这意味着患者进行了初次检查和复查。两名患者当时已在使用耳道棒状杆菌体外耐药的抗菌药物。给予强力霉素后，两名患者均有改善。耳道棒状杆菌可能在犬类皮炎中作为机会性病原体起作用，并且可能对基于混合感染中其他微生物药敏性的抗菌治疗无反应。偶尔，单独分离出的棒状杆菌可能具有致病性。
