Abstract: Le Wenjing, Su Xiaohong, Li Sai, Liu Yurong, Zhang Jinping, Zhu Xiaofeng, Wang Baoxi. Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing 210042, China Corresponding author: Su Xiaohong, Email: suxhong@yahoo.com 【Abstract】 Objective To establish two nested PCR assays for detection of Trichomonas vaginalis in urine samples from male patients with urethritis, and to evaluate their diagnostic value. Methods One thousand and eighty-eight male patients with urethritis were enrolled from sexually transmitted disease （STD） clinic in the Hospital of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College between April 2011 and December 2013. Urethral swabs were collected followed by smear testing, wet mount microscopic examination of Trichomonas vaginalis, and cultivation of Neisseria gonorrhoeae. Urine specimens were also obtained from these patients followed by DNA extraction. Two nested PCR assays were developed and performed to amplify the repeat genomic sequence and β-tubulin gene of Trichomonas vaginalis. Results Trichomonas vaginalis was detected in none of these swab specimens by wet mount microscopy, but in 29 （2.67%） of the urine specimens by either of the two nested PCR assays. Moreover, the positive specimens detected by the two nested PCR assays were completely consistent. Conclusion Compared with wet mount microscopy, nested PCR has higher sensitivity and specificity in detection of Trichomonas vaginalis in urine samples from male patients.

Key words: Urethritis, Trichomonas vaginalis, Polymerase chain reaction