Hjorth Sofie Vetli, Björnelius Eva, Lidbrink Peter, Falk Lars, Dohn Birthe, Berthelsen Lene, Ma Liang, Martin David H, Jensen Jørgen Skov
Mycoplasma Laboratory, Statens Serum Institut, DK-2300 Copenhagen S, Denmark.
J Clin Microbiol. 2006 Jun;44(6):2078-83. doi: 10.1128/JCM.00003-06.
Mycoplasma genitalium causes male nonchlamydial, nongonococcal urethritis and is associated with cervicitis and pelvic inflammatory disease in women. Epidemiological studies indicate that M. genitalium is sexually transmitted, and the aim of the present study was to further substantiate this by means of a DNA typing system. A typing assay based on a diagnostic mgpB gene PCR was developed, evaluated, and applied directly to urogenital specimens. The assay had a low limit of detection and hence a high typeability. Sequences of isolates from 52 unrelated patients were divided into 29 different sequence types, giving a discriminatory index of 0.95. Two to six M. genitalium-positive specimens were collected from each of 44 patients over a median interval of 56 days (range, 11 to 1,395). Forty had the same sequence type in consecutive specimens. Specimens collected from two men were repeatedly positive at intervals of 472 and 1,395 days, respectively, but the sequence types had changed. A new strain was introduced in one sexual dyad, and the sequence types changed subsequently. Seventy-nine M. genitalium-positive specimens from 19 couples were investigated, and all partners initially had concordant sequence types, but one couple had discordant types at one time point before a newly introduced strain took over. The present typing system is simple and reproducible and has an excellent discriminatory capacity which might prove useful in studies of sexual networks and for evaluation of treatment failures. In the laboratory, this system may document the uniqueness of newly isolated M. genitalium strains.
生殖支原体可引起男性非衣原体、非淋菌性尿道炎，并与女性宫颈炎和盆腔炎相关。流行病学研究表明生殖支原体通过性传播，本研究的目的是通过DNA分型系统进一步证实这一点。开发了一种基于诊断性mgpB基因PCR的分型检测方法，进行了评估，并直接应用于泌尿生殖系统标本。该检测方法检测限低，因此分型能力高。来自52例无亲属关系患者的分离株序列分为29种不同的序列类型，鉴别指数为0.95。在44例患者中，每位患者在中位间隔56天（范围11至1395天）内收集了2至6份生殖支原体阳性标本。40例患者连续标本具有相同的序列类型。从两名男性收集的标本分别在472天和1395天的间隔期反复呈阳性，但序列类型发生了变化。在一对性伴侣中引入了一种新菌株，随后序列类型发生了变化。对来自19对夫妇的79份生殖支原体阳性标本进行了研究，所有伴侣最初的序列类型一致，但在一种新引入的菌株占据主导之前，有一对夫妇在一个时间点序列类型不一致。目前的分型系统简单且可重复，具有出色的鉴别能力，这可能在性网络研究和治疗失败评估中有用。在实验室中，该系统可以证明新分离的生殖支原体菌株的独特性。
