Chlamydia trachomatis is the world's most prevalent bacterial sexually transmitted infection and leading infectious cause of blindness, yet it is one of the least understood human pathogens, in part due to the difficulties of in vitro culturing and the lack of available tools for genetic manipulation. Genome sequencing has reinvigorated this field, shedding light on the contemporary history of this pathogen. Here, we analyze 563 full genomes, 455 of which are novel, to show that the history of the species comprises two phases, and conclude that the currently circulating lineages are the result of evolution in different genomic ecotypes. Temporal analysis indicates these lineages have recently expanded in the space of thousands of years, rather than the millions of years as previously thought, a finding that dramatically changes our understanding of this pathogen's history. Finally, at a time when almost every pathogen is becoming increasingly resistant to antimicrobials, we show that there is no evidence of circulating genomic resistance in C. trachomatis.
Human papillomaviruses (HPV) infection in benign laryngeal papillomas is well established. The vast majority of recurrent respiratory papillomatosis lesions are due to HPV types 6 and 11. Human papillomaviruses are small non-enveloped viruses (>8 kb), that replicate within the nuclei of infected host cells. Infected host basal cell keratinocytes and papillomas arise from the disordered proliferation of these diVerentiating keratinocytes. Surgical debulking of papillomas is currently the treatment of choice; newer surgical approaches utilizing microdebriders are replacing laser ablation. Surgery aims to secure an adequate airway and improve and maintain an acceptable quality of voice. Adjuvant treatments currently used include cidofovir, indole-3-carbinol, ribavirin, mumps vaccine, and photodynamic therapy. The recent licensing of prophylactic HPV vaccines is a most interesting development. The low incidence of RRP does pose signiWcant problems in recruitment of suYcient numbers to show statistical signiWcance. Large multi-centre collaborative clinical trials are therefore required. Even so, suYcient clinical follow-up data would take several years.
Objective:To determine whether patients with genital warts carry human papillomavirus (HPV) DNA on their fingers. Methods: 14 men and eight women with genital warts had cytobrush samples taken from genital lesions, finger tips, and tips of finger nails. Samples were examined for the presence of HPV DNA by the polymerase chain reaction. Results: HPV DNA was detected in all female genital samples and in 13/14 male genital samples. HPV DNA was detected in the finger brush samples of three women and nine men. The same HPV type was identified in genital and hand samples in one woman and five men. Conclusion: This study has identified hand carriage of genital HPV types in patients with genital warts. Although sexual intercourse is considered the usual mode of transmitting genital HPV infection, our findings raise the possibility of transmission by finger-genital contact. (Sex Transm Inf 1999;75:317-319)
Urethral and endocervical swabs and self-collected vaginal swabs (SCVSs) and urine specimens are all used as samples for diagnosis of urogenital infection with Chlamydia trachomatis. We have now determined chlamydial organism load in matched specimens from different anatomic sites and examined its relation to clinical signs and symptoms in men and women. Organism load was measured with assays based on the ligase chain reaction or real-time PCR analysis. The mean organism loads in 58 infected men were 1,200 and 821 elementary bodies (EBs) per 100 l of sample for first-void urine (FVU) and urethral swabs, respectively (P > 0.05). Organism load in FVU samples or urethral swabs was positively associated with symptoms (P < 0.01) and clinical signs (P < 0.01) in men. The mean organism loads in 73 infected women were 2,231, 773, 162, and 47 EBs/100 l for endocervical swabs, SCVSs, urethral swabs, and FVU samples, respectively (P < 0.001 for each comparison). Only the presence of multiple symptoms or clinical signs was associated with organism load in women. These results show that FVU is a suitable noninvasive sample type for men, given the fact that its chlamydial load did not differ significantly from that of urethral swabs. Given their higher organism load compared with FVU, SCVSs are the preferred noninvasive sample type for women.Urogenital infection with Chlamydia trachomatis is the most commonly reported bacterial sexually transmitted infection (STI) and continues to be a major public health problem worldwide (4, 35). Given that most chlamydial infections are asymptomatic in both men and women, they often remain undiagnosed and untreated and therefore provide a reservoir for the disease (33). Infection of the upper genital tract may lead to complications, such as epididymitis in men and pelvic inflammatory disease in women. The inflammation and subsequent tissue scarring associated with the latter can lead to more serious sequelae (4).Effective control of chlamydial infection within a population requires early diagnosis and prompt treatment of asymptomatic individuals (28). Targeted and regular screening is also recommended for people in high-risk groups or with a past history of genital chlamydial infection (14). The most common sites of infection in women are the cervix and urethra. Infected cells are shed from the endocervix into the vagina and are present in vaginal secretions. Infected epithelial cells from the urethra and the associated C. trachomatis elementary bodies (EBs) can also be detected in first-void urine (FVU) (3, 16). Potentially suitable clinical specimens for detection of chlamydial infection in women thus include urethral, vaginal, and endocervical swabs, self-inserted tampons, and FVU samples (3, 12). For screening programs, noninvasive specimens, such as vaginal swabs, tampons, and FVU, are preferable to invasive urethral and endocervical swabs because they overcome several barriers associated with the traditional diagnostic pathway (5, 11). Sensitivity of C. trachomatis detection with vag...
Influence of ovarian hormones on urogenital infection C SonnexNumerous studies have examined the influence of hormones on infectious diseases and there is now a wealth of data relating to the more specific eVect of the sex hormones, oestrogen and progesterone, on urogenital infections. The interaction between these hormones and the immune system is complex and the variation of hormonal eVect between species further complicates the true picture as related to humans. Although it is diYcult therefore to draw general conclusions regarding predominant eVects of specific hormones, there is the suggestion that oestrogen enhances the pathogenicity of many urogenital micro-organisms. Our understanding of the influential role played by sex hormones in disease pathogenesis is at an early stage and illustrates well the importance of drawing together and interpreting as a whole both epidemiological and molecular studies. (Sex Transm Inf 1998;74:11-19)
We have developed and validated a nested real-time PCR (NRT-PCR) for the genotyping of Chlamydia trachomatis and used it specifically for the typing of either eight genovars from D to K or three genovars of lymphogranuloma venereum (LGV). The 11 probes used in the NRT-PCR correctly identified the DNA from D to K and LGV reference strains and did not cross-react with the DNA from 26 strains representing the bacterial pathogens and commensals of the oropharynx, genital tract, and rectum. The NRT-PCR had a 95% probability of detection at four genome copies (confidence interval, three to six copies) of C. trachomatis per reaction. One hundred cervical and urethral swab specimens containing C. trachomatis DNA from 63 women and 37 men were used to validate the method. The results from the NRT-PCR and the DNA sequencing of amplicons generated from the omp1 gene showed 100% correlation for these samples. The assay also identified the LGV-II genotype in 24 of 48 rectal swab specimens containing C. trachomatis DNA that were obtained from men having sex with men. The Sexually Transmitted Bacteria Reference Laboratory, London, independently confirmed these results using group-specific LGV real-time PCR and restriction fragment length polymorphism analysis. Compared with the NRT-PCR, non-NRT-PCR was found to be less sensitive: it typed C. trachomatis DNA in only 80% of the genital samples and 90% of the rectal swab samples. This is the first successful demonstration of the use of real-time PCR for the genotype-specific typing of C. trachomatis strains that cause sexually transmitted diseases.
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