綜說外耳炎相關之酵母菌抗藥性機制與治療失敗

Review of the Mechanisms of Antifungal Agents in Yeast and the Cause of Treatment Failure Associated Otitis Externa in Dogs

謝博揚(Bo-Young Hsieh) ； 余章游(Chang-You Yu) ； 蘇耀期(Yao-Chi Su) ； 賴治民(Jyh-Mirn Lai)

《嘉義大學通識學報》 9期 (2012/01) Pp. 159-176

https://doi.org/10.7042/JYDXTSXB.201201.0159

摘要

犬外耳炎（canine otitis externa）為臨床上常見疾病，因應治療方式包括耳道的清潔及抗微生物藥劑（或）併用抗炎症藥物。然而臨床上有部份病例經處置後，仍無法達到預期的結果。繼發性微生物病原，如Malassezia spp.會因耳道內微環境的改變，造成菌叢過度生長而導致外耳炎的惡化。外耳炎常用之抗真菌劑，如ketoconazole、intraconazole等azoles，可以調節Malassezia的生長。Malassezia spp.可能產生的抗藥性機制包括藥物的排出幫浦、改變藥物之目標酵素，及改變細胞膜的組成。本文首先討論犬外耳炎治療的問題，進而指出酵母菌群之藥物感受性現況及可能之相關抗藥性基因及其機制。

關鍵字

犬外耳炎 ； Malassezia ； 抗真菌劑 ； 抗藥性機制

並列摘要

Canine otitis externa is a common disease seen by veterinarians. The infection can often be treated by cleaning ear canals and applying antimicrobial agents with/out anti-inflammatory drugs. However, not all cases can be treated successfully. When a dog is infected, the dynamic change of the micro-environment in its ear canal often results in an overgrowth of normal flora, like a yeast called Malassezia, and worsens the condition of otitis externa. Commonly used antifungal agents, such as ketoconazole and intraconzaole of the azole group, can regulate the growth of yeasts. But yeasts have developed certain resistance mechanisms against azoles, such as increasing the number of efflux pumps, changing the enzymes required to survive, and modifying the structure of their cell membranes. This paper discusses a number of problems related to treating otitis externa in dogs, studies which discovered the antimicrobial resistant Malassezia and Candida of ear canal origin, and introduces a few possible antimicrobial resistance mechanisms and genes against azoles.

並列關鍵字

canine otitis externa ； Malasseiza ； antifungal agents ； drug resistant mechanism

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