Impact of Chlamydia trachomatis in the reproductive setting: British Fertility Society Guidelines for practice

Chlamydia trachomatis infection of the genital tract is the most common sexually transmitted infection and has a world-wide distribution. The consequences of infection have an adverse effect on the reproductive health of women and are a common cause of infertility. Recent evidence also suggests an adverse effect on male reproduction. There is a need to standardise the approach in managing the impact of C. trachomatis infection on reproductive health. We have surveyed current UK practice towards screening and management of Chlamydia infections in the fertility setting. We found that at least 90% of clinicians surveyed offered screening. The literature on this topic was examined and revealed a paucity of solid evidence for estimating the risks of long-term reproductive sequelae following lower genital tract infection with C. trachomatis. The mechanism for the damage that occurs after Chlamydial infections is uncertain. However, instrumentation of the uterus in women with C. trachomatis infection is associated with a high risk of pelvic inflammatory disease, which can be prevented by appropriate antibiotic treatment and may prevent infected women from being at increased risk of the adverse sequelae, such as ectopic pregnancy and tubal factor infertility. Recommendations for practice have been proposed and the need for further studies is identified

Real-time polymerase chain reaction shows that density centrifugation does not always remove Chlamydia trachomatis from human semen

Objective: To evaluate the efficiency of sperm washing procedures to remove Chlamydia trachomatis from semen both in clinical samples and experimental inoculations. Design: Laboratory-based study. Setting: Research laboratory in a university hospital. Patient(s): One hundred men attending for diagnostic semen analysis as part of infertility investigations and three sperm donors providing ejaculates for research purposes. Main Outcome Measure(s): Number of DNA copies of C. trachomatis, infectivity in an HeLa cell monolayer, and immunofluorescence. Result(s): Of the 100 semen samples examined, 13 contained detectable levels of C. trachomatis DNA (675–15,920 copies/mL) and in only 7 was this completely removed after sperm washing. In the remaining six DNA-positive samples, the number of copies in the postwash preparation ranged from 36–455 per mL. Experimental inoculations found that postwash preparations containing C. trachomatis DNA as low as 61 copies/mL were able to establish an infection in vitro. Conclusion(s): Undiagnosed C. trachomatis infections in men attending for assisted conception could potentially lead to infection or contamination of the IVF culture system as sperm washing methods are not 100% effective

Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A

<div><p>Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of “immune exclusion” based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers–a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates.</p></div