解脲支原体药敏与tetM基因检测及生物群的研究

目的：了解泌尿生殖道支原体的耐药性机理，指导临床治疗。方法：采用微量肉汤稀释法测定281株UU对5种抗菌药物的最低抑菌浓度（MIC），用PCR法扩增tetM基因并酶切，用UU MB抗原基因引物对 tetM基因阳性UU株进行生物群的研究。结果：281UU 82株对四环素MIC为16－256ug/ml,39株为8ug/ml，7株为4ug/ml,153株MIC＜4ug/ml；121株MIC大于等于8ug/ml及2株MIC＝4ug/ml者均出现377bp tetM基因阳性带；阳性检测率为43．77％。158株UU MIC小于等于4ug/ml未见类似扩增带，扩增产物用Hpa II酶切和电泳分析，均产生279bp和98bp两个特异性片段。281株UU用群特异性PCR分析，生物群1有166株，生物群2有115株，123株tetM阳性UU株，属生物群1，2者分别有54株和69株，分别占32．53％（54／166）和60．0％（69／115）（X2＝7．94，P＜0．05），结论：（1）PCR技术检测泌尿生殖道感染患者UU耐药性tetM基因具有特异，敏感，快速等优点；（2）载有tetM基因的UU株可能成为四环素耐药株，应进行监测及随访；（3）我国衡阳地区UU四环素耐药株以生物群2占优势。

Study on DrugsSusceptibility, tetM Gene Determination and Biotypes of Ureaplasma Urealyticum

Objective To monitor resistance of urogenital mycoplasma periodically, and to instruct rational application of antibiotics clinically. Methods The minimal inhibitory concentrations(MICs) of 281 strains UU to 5 kinds of antimicrobial agents were determined using microbroth dilution assay, the tetM gene in the isolates was detected by PCR and the PCR products were digested by Hpa Ⅱ restrictive endonuclease. PCR analysis was used to sutdy the biotypes of UU with tetM gene with primers derived from MB antigen gene. Results Of 281 strains UU tested,82 strains,which MIC were≥16～256μg/ml,39 MIC=8μg/ml,7MIC= 4μg/ml and 153,MIC＜4μg/ml. A 377bp PCR amplified product was found in 121 strains UU which MIC≥8μg/ml,2 strains, MIC=4μg/ml also gave PCR products of the appropriate size. The positive rate of tetM was 43.77%. 158 strains MIC≤4μg/ml failed to give PCR products. The products of PCR were digested with restriction enzyme and gave rise to 279bp and 98bp two fragments. Biotype-specific PCR was used for 281 strains UU, 166 strains were classified as biotype 1, and 115strains were classfied as biotype 2.123 strains UU with tetM gene, the strains classified as biotype 1 and biotype 2 were 54and 69respectively, the percentage was 32.53% (54/166) and 60.0% (69/115) respectively. Conclusion ①PCR technique has specific,sensitive, rapid advantages for tetM gene detection of UU in patients with urogenital infections. ②UU strains carrying tetM gene might become drug resistent ones which should be monitored and followed up with MIC determination. ③Biotype 2. is the dominant srains of the tetracycline-resistant UU in Heng Yang.