PDF(Pubmed)
Abstract：
BACKGROUND: Many clinicians prescribe antifungal agents to treat canine otitis externa (OE). However, studies evaluating the antifungal effects of N-acetylcysteine (NAC) and its combinations are limited.
OBJECTIVE: The aim of this study was to evaluate the antifungal effects of NAC alone and in combination with other antifungal agents against Malassezia pachydermatis isolated from canine OE.
METHODS: M. pachydermatis samples were collected from 13 dogs with OE. The final concentration of the inoculum suspensions of M. pachydermatis was 1-5 × 106 colony forming units/mL. The concentrations of the test compounds ketoconazole (KTZ), terbinafine (TER), nystatin (NYS) and NAC were 0.02-300 µg/mL, 0.04-80 µg/mL, 0.16-40 µg/mL and 1.25-20 mg/mL, respectively. The minimum inhibitory concentration (MIC) was measured to evaluate the susceptibility of the M. pachydermatis to KTZ, TER, NYS and NAC. The checkerboard testing method and fractional inhibitory concentration index were used to evaluate the effect of NAC in combination with KTZ, TER and NYS against M. pachydermatis.
RESULTS: The MIC90 values of M. pachydermatis were 4.6875-9.375 µg/mL, 1.25 µg/mL, 5-10 µg/mL and 10 mg/mL for KTZ, TER, NYS and NAC, respectively. The synergistic effects of KTZ, TER and NYS with NAC were identified in 0/13, 2/13 and 0/13 isolates, respectively.
CONCLUSIONS: NAC had an antifungal effect against M. pachydermatis but did not exert synergistic effects when used with KTZ, TER and NYS. Thus, the use of NAC alone as a topical solution could be considered an effective treatment option for canine OE involving M. pachydermatis.
OBJECTIVE: The aim of this study was to evaluate the antifungal effects of NAC alone and in combination with other antifungal agents against Malassezia pachydermatis isolated from canine OE.
METHODS: M. pachydermatis samples were collected from 13 dogs with OE. The final concentration of the inoculum suspensions of M. pachydermatis was 1-5 × 106 colony forming units/mL. The concentrations of the test compounds ketoconazole (KTZ), terbinafine (TER), nystatin (NYS) and NAC were 0.02-300 µg/mL, 0.04-80 µg/mL, 0.16-40 µg/mL and 1.25-20 mg/mL, respectively. The minimum inhibitory concentration (MIC) was measured to evaluate the susceptibility of the M. pachydermatis to KTZ, TER, NYS and NAC. The checkerboard testing method and fractional inhibitory concentration index were used to evaluate the effect of NAC in combination with KTZ, TER and NYS against M. pachydermatis.
RESULTS: The MIC90 values of M. pachydermatis were 4.6875-9.375 µg/mL, 1.25 µg/mL, 5-10 µg/mL and 10 mg/mL for KTZ, TER, NYS and NAC, respectively. The synergistic effects of KTZ, TER and NYS with NAC were identified in 0/13, 2/13 and 0/13 isolates, respectively.
CONCLUSIONS: NAC had an antifungal effect against M. pachydermatis but did not exert synergistic effects when used with KTZ, TER and NYS. Thus, the use of NAC alone as a topical solution could be considered an effective treatment option for canine OE involving M. pachydermatis.
摘要：
背景：许多临床医生处方抗真菌药物来治疗犬外耳炎（OE）。然而,评估N-乙酰半胱氨酸（NAC）及其组合的抗真菌作用的研究有限。
目的：本研究的目的是评估单独使用NAC以及与其他抗真菌药物联合使用对从犬OE中分离的马拉色菌的抗真菌作用。
方法：M.从13只患有OE的狗收集厚皮动物样品。厚皮分枝杆菌的接种物悬浮液的最终浓度为1-5×106菌落形成单位/mL。试验化合物酮康唑(KTZ)的浓度,特比萘芬（TER），制霉菌素（NYS）和NAC为0.02-300µg/mL，0.04-80µg/mL，0.16-40微克/毫升和1.25-20毫克/毫升，分别。测量最小抑制浓度（MIC）以评估厚皮分枝杆菌对KTZ的敏感性，TER,NYS和NAC。采用棋盘测试方法和分数抑制浓度指数评价NAC联合KTZ的效果,TER和NYS对抗厚皮分枝杆菌。
结果：厚皮分枝杆菌的MIC90值为4.6875-9.375µg/mL，1.25微克/毫升，5-10µg/mL，KTZ为10mg/mL，TER,NYS和NAC,分别。KTZ的协同效应，在0/13、2/13和0/13分离株中鉴定出具有NAC的TER和NYS，分别。
结论：NAC对厚皮分枝杆菌具有抗真菌作用，但与KTZ一起使用时没有协同作用，TER和NYS。因此，单独使用NAC作为局部溶液可被认为是涉及厚皮分枝杆菌的犬OE的有效治疗选择.
目的：本研究的目的是评估单独使用NAC以及与其他抗真菌药物联合使用对从犬OE中分离的马拉色菌的抗真菌作用。
方法：M.从13只患有OE的狗收集厚皮动物样品。厚皮分枝杆菌的接种物悬浮液的最终浓度为1-5×106菌落形成单位/mL。试验化合物酮康唑(KTZ)的浓度,特比萘芬（TER），制霉菌素（NYS）和NAC为0.02-300µg/mL，0.04-80µg/mL，0.16-40微克/毫升和1.25-20毫克/毫升，分别。测量最小抑制浓度（MIC）以评估厚皮分枝杆菌对KTZ的敏感性，TER,NYS和NAC。采用棋盘测试方法和分数抑制浓度指数评价NAC联合KTZ的效果,TER和NYS对抗厚皮分枝杆菌。
结果：厚皮分枝杆菌的MIC90值为4.6875-9.375µg/mL，1.25微克/毫升，5-10µg/mL，KTZ为10mg/mL，TER,NYS和NAC,分别。KTZ的协同效应，在0/13、2/13和0/13分离株中鉴定出具有NAC的TER和NYS，分别。
结论：NAC对厚皮分枝杆菌具有抗真菌作用，但与KTZ一起使用时没有协同作用，TER和NYS。因此，单独使用NAC作为局部溶液可被认为是涉及厚皮分枝杆菌的犬OE的有效治疗选择.
