Hormonal factors and the laboratory detection of Chlamydia trachomatis in women: implications for screening?

Diagnostic tests and specimens used to screen for Chlamydia trachomatis in genitourinary medicine clinics in the United Kingdom

This questionnaire study looked at the diagnostics tests and specimens used to screen for Chlamydia trachomatis in UK genitourinary medicine (GUM) clinics. Replies were received from 70% (185/265) of clinics. Half used only one site to screen women. One-third took anal swabs from patients who had anal sex and 10% took oropharyngeal swabs from patients who had oral sex.

Immunoassays were used to screen men for chlamydia in 86% of the clinics and women in 88%. Only 60% of male and 62% of female immunoassays were supplemented by a second test. Six per cent of clinics used molecular technique (MT) to screen men and 4% to screen women and 4% were trying to acquire it.

Culture was not available to 58% of clinics. MT was not available to 81%, 89% of which was due to non provision locally and/or cost. Only 7% of clinicians thought that using MT for screening was unnecessary. There were significant differences in the availability of the technique between large academic and small clinics. A national review of GUM strategies to screen for C. trachomatis with adequate funding is urgently needed.

Chlamydia detection during the menstrual cycle: a cross-sectional study of women attending a sexual health service

Background

We investigated the detection of chlamydia at different stages of the menstrual cycle.

Methods

Electronic medical records for women attending Melbourne Sexual Health Centre between March 2011 and 31^st December 2012, who were tested for chlamydia by nucleic acid amplification of high vaginal, cervical, or urinary samples, and who recorded a date of last normal menstrual period (LNMP) between 0–28 days were included in the analysis. Logistic regression was used to calculate adjusted odds ratio (aOR) and 95% confidence intervals (CI) for the association of chlamydia with menstrual cycle adjusted by demographics and behavioural variables. Chlamydia and beta globin load were determined on those with stored samples.

Results

Of the 10,017 consultations that included a test for chlamydia and a valid LNMP, there were 417 in which chlamydia was detected. The proportion of samples with chlamydia was greater in the luteal phase (4.8%, 184/3831) than in the follicular phase (3.4%, 233/6816) both in the crude (OR 1.29 95%CI 1.1–1.6, p = 0.01) and adjusted odds ratio (aOR) 1.4 (95%CI 1.1–1.8, p = 0.004). Among women using hormonal contraception, there was no significant association with the luteal phase of the menstrual cycle (aOR 1.3, 95%CI 0.9, 1.8, p = 0.18). Among women not using hormonal contraception, there was a significant association with the luteal phase (aOR 1.6, (95% CI 1.1–2.3, p = 0.007). The chlamydia load was not significantly different in the 329 positive stored samples in weeks 3 and 4 vs weeks 1 and 2 for any site (P>0.12).

Conclusions

The higher detection of chlamydia detection in the luteal phase of the menstrual cycle in only those not taking hormonal contraception suggest that hormonal factors influence chlamydia detection. The absence of a significantly highly chlamydia load in women during the luteal phase raises questions about the mechanism.

Hormonal contraceptive use and risk of sexually transmitted infections: a systematic review

Previous research has suggested that hormonal contraceptive users, compared with nonusers, may be at increased risk for acquiring sexually transmitted infections (STIs). We searched the MEDLINE and EMBASE databases for all articles from January 1966 through February 2005 for evidence relevant to all hormonal contraceptives and STIs (including cervical chlamydial and gonococcal infection, human papillomavirus, trichomoniasis, herpes and syphilis). We used standard abstract forms and grading systems to summarize and assess the quality of 83 identified studies. Studies of combined oral contraceptive and depot medroxyprogesterone use generally reported positive associations with cervical chlamydial infection, although not all associations were statistically significant. For other STIs, the findings suggested no association between hormonal contraceptive use and STI acquisition, or the results were too limited to draw any conclusions. Evidence was generally limited in both amount and quality, including inadequate adjustment for confounding, lack of appropriate control groups and small sample sizes. The observed positive associations may be due to a true association or to bias, such as differential exposure to STIs by contraceptive use or increased likelihood of STI detection among hormonal contraceptive users.

Characterization of estrogen-responsive epithelial cell lines and their infectivity by genital Chlamydia trachomatis

Chlamydial attachment and infectivity in vitro and ascending disease and sequelae in vivo have been reported to be enhanced/modulated by estrogen. Endometrial carcinoma cell lines Ishikawa and HEC-1B and the breast cancer lines MCF-7 and HCC-1806 were examined for Chlamydia trachomatis E infectivity. Estrogen receptor (ER) presence was confirmed by Western blot and qRT-PCR analyses. FACS analysis was used to determine the percent of plasma membrane-localized ERs (mERs), and their activity was tested by estrogen binding and competitive estrogen antagonists assays. Chlamydiae grew in all cell lines with HEC (90%) >> MCF-7 (57%)>Ishikawa (51%) >> HCC-1806 (20%). The cell line ER isoform composition was re-defined as: ERalpha + ERbeta + for MCF-7, HCC-1806 and Ishikawa; and ERbeta only for HEC-1B. HeLa cells were also tested and found to express ERbeta, but not ERalpha. A small percentage of both ERs were surface-exposed and functionally active. The endometrium-predominant ERbeta isoform was found in all cell lines, including those most representative of the common sites of C. trachomatis infection. Thus, the role of chlamydial attachment/infectivity will now be analyzed in ERbeta+and-isogenic HEC-1B cells.

Estradiol regulates susceptibility following primary exposure to genital herpes simplex virus type 2, while progesterone induces inflammation

We report here that sex hormones modulate susceptibility to a sexually transmitted viral agent, herpes simplex virus type 2 (HSV-2), in a mouse model. Ovariectomized mice were administered either saline (control), estradiol (E(2)), progesterone (P(4)), or a combination of both estradiol and progesterone (E+P) and infected intravaginally with HSV-2. With an inoculation dose of 10(5) PFU, the saline- and P(4)-treated mice were found to be highly susceptible to genital HSV-2 infection. Both groups had extensive pathology and high viral titers in vaginal secretions, and 100% of mice succumbed by day 4 postinfection. E(2)-treated mice were protected from HSV-2 infection at the same dose and did not display any vaginal pathology or viral shedding. There was a slow progression of genital pathology in the combination hormone-treated group, along with prolonged viral shedding; 80% of animals succumbed by day 13. With lower inoculation doses of 10(3) and 10(2) PFU, 50 and 100%, respectively, of the combination hormone-treated mice survived. Localization of HSV-2 infection showed extensive infection in the vaginal epithelium of P(4)- and saline-treated animals within 24 h of inoculation. E(2)-treated animals were clear of infection, while the E+P-treated group had focal infection at 24 h that had progressed extensively by day 3. Infection was accompanied by persistent inflammation and infiltration of neutrophils in the P(4)-treated group. An analysis of the genes in the vaginal tissue showed that inflammation in the P(4)-treated group correlated with local induction of chemokines and chemokine receptors that were absent in the E(2)-treated mice and in uninfected P(4)-treated mice. The results show that sex hormones regulate initiation of infection and immune responses to genital HSV-2 infection.

Protection against genital herpes infection in mice immunized under different hormonal conditions correlates with induction of vagina-associated lymphoid tissue

The present study was undertaken to examine the effect of the hormonal environment on immunization with an attenuated strain of herpes simplex virus type 2 (HSV-2 TK(-)) and subsequent protection against challenge. Ovariectomized mice were administered saline (S; control), estradiol (E(2)), progesterone (P(4)), or a combination of estradiol and progesterone (E+P) and immunized intravaginally (IVAG) with HSV-2 TK(-). Three weeks later, the immunized mice were challenged IVAG with wild-type HSV-2. Mice that were immunized following E treatment were not protected, whereas complete protection against the challenge was seen in mice from the S- and P(4)-treated groups. In the P(4)-treated group, 15% of mice developed chronic pathology following TK(-) immunization. Interestingly, about 40% of the E+P-treated mice were also protected. Upon examination of viral shedding in the vaginal secretions, it was clear that protection against challenge was dependent on the ability of the TK(-) virus to cause productive genital infection under different hormonal conditions. In the protected mice (the S and P groups and part of the E+P group), induced vagina-associated lymphoid tissues composed of CD11c(+) dendritic cells and CD3(+) and CD4(+) T cells were formed transiently in the vaginal lamina propria from day 2 to day 5 postchallenge. These aggregates were absent in the unprotected mice (the E group and part of the E+P group). Significant HSV-2-specific activation of lymphocytes was observed in the local draining lymph nodes of protected mice. This response was absent in the unprotected groups. High titers of gB-specific local immunoglobulin A (IgA) antibodies were present in the vaginal secretions of S- and P(4)-treated immunized mice following HSV-2 challenge. The S-treated group of mice also had high gB-specific IgG titers. These studies show that sex hormones modify the induction of protective immune responses following IVAG immunization.

Chlamydia trachomatis in the United Kingdom: a systematic review and analysis of prevalence studies

OBJECTIVES

To undertake a systematic review to obtain estimates of genital Chlamydia trachomatis prevalence in various populations in the United Kingdom and Ireland; to determine which populations have the highest rates of infection; and to explore the most important determinants of infection.

METHODS

Electronic databases were searched using the keywords "chlamydia" and "England," "Wales," "UK," "Scotland," "Ireland," or "Britain." Additional unpublished data and references were solicited from experts. Studies were included in the analysis if C trachomatis prevalence was reported, and if they met inclusion criteria. Nine variables identified as potentially important descriptors of chlamydia prevalence were extracted from each study and analysed using various logistic regression models. Only studies reporting prevalence in female populations were included in the models, because there were few data from males.

RESULTS

357 studies were identified using the search methods, 90 of which met inclusion criteria, and 19 of which contributed to the final model. The most influential variables on prevalence were age and setting of the population tested. In general practice surgeries, the under 20 year old age group had an estimated prevalence of 8.1% (95% CI 6.5 to 9.9), 20-24 year olds 5.2% (95% CI 4.3 to 6.3), 25-29 year olds 2.6% (95% CI 2.0 to 3.3), decreasing to 1.4% (95% CI 1.0 to 1.9) in those aged over 30 years. Overall, healthcare settings had higher prevalence estimates than population based studies. For example, among under 20 year olds, estimates were 17.3% (95% CI 13.6 to 21.8) in genitourinary medicine clinics, 12.6% (95% CI 6.4 to 23.2) in antenatal clinics, 12.3% (95% CI 9.8 to 15.3) in termination of pregnancy clinics, 10.7% (95% CI 8.3 to 13.8) in youth clinics, 10.0% (95% CI 8.7 to 11.5) in family planning clinics, and 8.1% (95% CI 6.5 to 9.9) in general practice, compared to 5.0% (95% CI 3.2 to 7.6) in population based studies. The type of test, specimen used, date, and location of test were not strongly associated with chlamydia prevalence.

CONCLUSION

The chlamydia prevalence estimates by age and setting from the model may be used to inform chlamydia screening strategies. The systematic review revealed much heterogeneity in the studies identified, but with clear patterns of prevalence. It also indicated gaps in the knowledge about chlamydia prevalence in certain subgroups such as men and the general population.

Hormonal contraception can suppress natural antimicrobial gene transcription in human endometrium

OBJECTIVE

To determine the effect of hormonal contraception with a combined oral contraceptive pill and levonorgestrel intrauterine system on the expression of the natural antimicrobials secretory leukocyte protease inhibitor, beta-defensins 1 and 2, and granulysin in human endometrium.

DESIGN

Observational study.

SETTING

Day case ward in a department of obstetrics and gynecology.

PATIENT(S)

Fifty seven women undergoing gynecologic procedures for benign conditions; 24 received no contraception for more than 3 months, 20 received a combined oral contraceptive for more than 3 months, and 13 wore a levonorgestrel intrauterine system for more than 3 months.

MAIN OUTCOME MEASURE(S)

Endometrial samples were collected from all women. Messenger RNA was extracted and quantitative polymerase chain reaction was used to investigate expression of secretory leukocyte protease inhibitor, beta-defensin 1, beta-defensin 2, and granulysin. Immunohistochemistry for secretory leukocyte protease inhibitor was performed.

RESULT(S)

All antimicrobials varied cyclically. The level of secretory leukocyte protease inhibitor was maximal in the late secretory and menstrual phase, beta-defensin 1 in the mid secretory phase, granulysin in the late secretory phase, and beta-defensin 2 in the menstrual phase. Use of a combined oral contraceptive or levonorgestrel intrauterine system use decreased messenger RNA expression of beta-defensin 1 and 2 and granulysin but not secretory leukocyte protease inhibitor.

CONCLUSION(S)

Endogenous and exogenous sex-steroid hormones, in the form of a combined oral contraceptive or levonorgestrel intrauterine system, influence gene transcription of secretory leukocyte protease inhibitor, beta-defensin 1, beta-defensin 2, and granulysin in the endometrium.

Computerized planimetry versus clinical assessment for the measurement of cervical ectopia

OBJECTIVE

As part of a study to assess the role of cervical ectopia in the acquisition of cervical infections, we determined the reliability of cervical ectopia measurements made by computer planimetry and by clinical (visual) assessment.

STUDY DESIGN

We conducted pelvic examinations of 1004 women seeking contraceptive services at two health centers in Baltimore. After application of acetic acid, clinicians estimated the relative area of ectopia by visual inspection and took cervical photographs. Two independent raters measured the absolute and relative areas of ectopia from the digitized images by means of an analytic software program. Agreement levels between raters, between multiple readings by the same rater, and between the two measurement methods were quantified by means of the intraclass correlation coefficient and weighted kappa.

RESULTS

Intrarater agreement was excellent for computer planimetry measurements of the absolute (intraclass correlation coefficient, 0.97) and relative (intraclass correlation coefficient, 0.89) areas of ectopia. Interrater agreement was also high for computer planimetry measurements of the absolute (intraclass correlation coefficient, 0.83) and relative (intraclass correlation coefficient, 0.85) areas of ectopia. Agreement levels were moderate between clinician assessment and computer planimetry measurements of the relative area of ectopia (kappa = 0.48), but agreement was better when clinical assessment was limited to observations by a single, experienced clinician.

CONCLUSION

Measurement of cervical ectopia by computer planimetry was highly reliable and appears appropriate for assessment of the role of ectopia in the acquisition of cervical infections. Clinical assessment of cervical ectopia may be used when computer planimetry is not available.

Is bacterial vaginosis a sexually transmitted infection?

OBJECTIVES

To determine whether the risk factors associated with bacterial vaginosis (BV) are consistent with it being a sexually transmitted infection (STI) by comparing the characteristics of women with BV with those of women with infections recognised as being sexually and non-sexually transmitted.

METHODS

A prospective cross sectional study was conducted among female patients presenting for diagnosis at a genitourinary medicine clinic in Sheffield between January 1996 and September 1998. Demographic and behavioural characteristics were reported from patient records and a standardised questionnaire was administered. Risk factor models for BV, two STIs, and two non-STIs were compiled using a multivariable logistic regression analysis.

RESULTS

Among the 8989 females under 45 years eligible for analysis, the prevalence of BV was 12.9%. Risk factors associated with BV included some in common with gonorrhoea and Chlamydia trachomatis and some that were not associated with these two STIs. Risk factors common to BV and the STIs included having had more than one sexual partner in the past 3 months, having a history of a bacterial STI, being of black Caribbean ethnicity, and living in a deprived area. However, BV had a contrasting age profile, being most prevalent among those over the age of 30. BV was also more common in those who were divorced.

CONCLUSIONS

BV is associated with some factors related to the acquisition of gonorrhoea and Chlamydia trachomatis. However, infection is not only determined by those factors and therefore factors other than sexual activity may be important in the development of the condition.

Influence of ovarian hormones on urogenital infection

Numerous studies have examined the influence of hormones on infectious diseases and there is now a wealth of data relating to the more specific effect 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 effect between species further complicates the true picture as related to humans. Although it is difficult therefore to draw general conclusions regarding predominant effects 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.