Frequency of Chlamydia trachomatis in Ureaplasma-positive healthy women attending their first prenatal visit in a community hospital in Sapporo, Japan

<p>Abstract</p> <p>Background</p> <p>Although <it>Chlamydia trachomatis </it>is the most commonly reported pathogen that causes urogenital infection such as urethritis or cervicitis, <it>Ureaplasma parvum </it>and <it>Ureaplasma urealyticum</it>, which are commensals in the genital tract, have also now been recognized as contributors to urogenital infection. However, whether the presence of either <it>U. parvum </it>or <it>U. urealyticum </it>is related to that of <it>C. trachomatis </it>in the urogenital tract remains unknown. We therefore attempted to estimate by PCR the prevalence of <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum </it>in endocervical samples obtained from healthy women attending their first prenatal visit in Sapporo, Japan.</p> <p>Methods</p> <p>The samples were taken from 303 apparently healthy women, and the extracted DNAs (<it>n </it>= 280) were used for PCR detection targeting <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum</it>. Statistical analysis of the data was performed by Fisher's exact test.</p> <p>Results</p> <p>PCR detection revealed that the prevalence of <it>C. trachomatis, U. parvum </it>and <it>U. urealyticum </it>was 14.3% (40/280), 41.7% (117/280) and 8.9% (25/280), respectively. <it>C. trachomatis ompA </it>genotype D was most frequently identified. Surprisingly, either <it>C. trachomatis </it>or <it>Ureaplasma </it>spp. was detected in almost half of the healthy women. Mixed infection of <it>C. trachomatis </it>with either <it>U. parvum </it>or <it>U. urealyticum </it>was also observed in 9.2% (26/280) of the women. There was a significant association between <it>C. trachomatis </it>and either <it>U. parvum </it>(<it>p </it>= 0.023) or <it>Ureaplasma </it>total (<it>p </it>= 0.013), but not <it>U. urealyticum </it>(<it>p </it>= 0.275).</p> <p>Conclusion</p> <p>This study demonstrated that the presence of <it>Ureaplasma </it>had a significant effect on the presence of <it>C. trachomatis </it>in the genital tract of healthy women, suggesting that mixed infection is an important factor in bacterial pathogenesis in the genital tract.</p

Comparison between Culture and a Multiplex Quantitative Real-Time Polymerase Chain Reaction Assay Detecting Ureaplasma urealyticum and U. parvum

A novel multiplex quantitative real-time polymerase chain reaction (qPCR) for simultaneous detection of U. urealyticum and U. parvum was developed and compared with quantitative culture in Shepard’s 10 C medium for ureaplasmas in urethral swabs from 129 men and 66 women, and cervical swabs from 61 women. Using culture as the gold standard, the sensitivity of the qPCR was 96 % and 95 % for female urethral and cervical swabs, respectively. In male urethral swabs the sensitivity was 89%. The corresponding specificities were 100%, 87 % and 99%. The qPCR showed a linear increasing DNA copy number with increasing colour-changing units. Although slightly less sensitive than culture, this multiplex qPCR assay detecting U. urealyticum and U. parvum constitutes a simple and fast alternative to the traditional methods for identification of ureaplasmas and allows simultaneous species differentiation and quantitation in clinical samples. Furthermore, specimens overgrown by other bacteria using the culture method can be evaluated in the qPCR