Abstract:To investigate a rapid, specific and sensitive method to diagnose Trichophyton mentagrophytes infections in rabbits, a total of 63 clinical specimens were collected from rabbit with suspected dermatophytosis. These specimens were examined by both conventional diagnostic (direct microscopy and culture) method and real-time PCR assay, which were compared by sensitivity, specificity, positive and negative predictive value. The results showed that real-time PCR assay for Trichophyton mentagrophytes was positive in 86%, followed by direct microscopy(73%) and culture method(65%). Comparing with direct microscopy and culture method, real-time PCR assay had significantly higher sensitivity (100%vs 86.79%-77.35%) and negative predictive value (100% vs 64.17%-45.45%), while no significant differences were observed in specificity (90.90% vs 100%-100%) and positive predictive value (98.11% vs 100%-100%). In vitro culture is a specific diagnostic test, but is in poor sensitivity and long turnaround time of technique, with false negative results. Direct microscopy is a rapid diagnostic method but it lacks specificity and sensitivity. The specific result and short response time makes this real-time PCR assay very suitable as a routine diagnostic assay for Trichophyton mentagrophytes. It could advantageously replace the direct microscopy, but not the culture method.
沈洁, 刘月, 刘利强, 刘娜, 刘建钗, 刘彦威, 邢鑫. 兔须癣毛癣菌感染样本常规诊断与定量PCR诊断的比较研究[J]. 中国人兽共患病学报, 2016, 32(2): 165-168.
SHEN Jie, LIU Yue, LIU Li-qiang, LIU Na, LIU Jian-chai, LIU Yan-wei, XING Xin. Comparison of real-time PCR with conventional methods to diagnose Trichophyton mentagrophytes in clinical specimens from rabbits. Chinese Journal of Zoonoses, 2016, 32(2): 165-168.
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