Association of Chlamydia trachomatis infection with redetection of human papillomavirus after apparent clearance

Prevalence of co-infection with human papillomavirus and Chlamydia trachomatis and risk factors associated with cervical cancer in Congolese women

The human papillomavirus (HPV) is one of the most frequently diagnosed viruses in developing countries. Chlamydia trachomatis (CT) is an important cofactor in HPV-induced cervical cancer. Cervico-uterine smears were taken for cytology, and a total of 131 samples were analysed. HPV prevalence and CT were detected using specific primers (L1 gene and omp-1 gene). 23 (17.5 %) HPV-only samples were detected, CT-only positives were 10 (7.6 %). And HPV/CT co-infection was 13 (9.9 %). Identified risk factors associated with HPV/CT co-infection were risky sexual behaviour and cytology status. The prevalence of HPV and CT and their co-infection rates being high in our study population, may be an indicator of cervical cancer risk. Consequently, there is an urgent need to raise awareness and take appropriate precautions.

Expression of HPV-16 E6 and E7 oncoproteins alters Chlamydia trachomatis developmental cycle and induces increased levels of immune regulatory molecules

Introduction

Infection with Human Papillomavirus (HPV) is a recognized risk factor for Chlamydia trachomatis (CT) infection and vice versa. Coinfection of HPV and CT in women is a very common and usually asymptomatic finding that has been linked to increased risk of cervical cancer. It has been demonstrated that CT facilitates the entry of multiple high risk HPV genotypes, leading to damage of the mucosal barrier and interfering with immune responses and viral clearance, which ultimately favours viral persistence and malignant transformation. Although the facilitating effects elicited by CT infection on viral persistence have been reported, little is known about the consequences of HPV infection on CT development.

Methods

Herein, we took advantage of a genetically modified human cervical cell line co-expressing HPV-16 major oncogenic proteins E6 and E7, as an experimental model allowing to investigate the possible effects that HPV infection would have on CT development.

Results and discussion

Our results show that CT infection of HPV-16 E6E7 expressing cells induced an upregulation of the expression of E6E7 oncoproteins and host cell inhibitory molecules PD-L1, HVEM and CD160. Additionally, smaller chlamydial inclusions and reduced infectious progeny generation was observed in E6E7 cells. Ultrastructural analysis showed that expression of E6 and E7 did not alter total bacterial counts within inclusions but resulted in increased numbers of reticulate bodies (RB) and decreased production of infectious elementary bodies (EB). Our results indicate that during CT and HPV coinfection, E6 and E7 oncoproteins impair RB to EB transition and infectious progeny generation. On the other hand, higher expression of immune inhibitory molecules and HPV-16 E6E7 are cooperatively enhanced in CT-infected cells, which would favour both oncogenesis and immunosuppression. Our findings pose important implications for clinical management of patients with HPV and CT coinfection, suggesting that screening for the mutual infection could represent an opportunity to intervene and prevent severe reproductive health outcomes, such as cervical cancer and infertility.

Human Papillomavirus Intermittence and Risk Factors Associated With First Detections and Redetections in the Ludwig-McGill Cohort Study of Adult Women

BACKGROUND

We assessed the incidence and risk factors for first detection and redetection with the same human papillomavirus (HPV) genotype, and prevalence of cytological lesions during HPV redetections.

METHODS

The Ludwig-McGill cohort study followed women aged 18-60 years from São Paulo, Brazil in 1993-1997 for up to 10 years. Women provided cervical samples for cytology testing and HPV DNA testing at each visit. A redetection was defined as a recurring genotype-specific HPV positive result after 1 or more intervening negative visits. Predictors of genotype-specific redetection were assessed using adjusted hazard ratios (aHR) with Cox regression modeling.

RESULTS

In total, 2184 women contributed 2368 incident HPV genotype-specific first detections and 308 genotype-specific redetections over a median follow-up of 6.5 years. The cumulative incidence of redetection with the same genotype was 6.6% at 1 year and 14.8% at 5 years after the loss of positivity of the first detection. Neither age (aHR 0.90; 95% confidence interval [CI], .54-1.47 for ≥45 years vs < 25 years) nor new sexual partner acquisition (aHR 0.98; 95% CI, .70-1.35) were statistically associated with genotype-specific redetection. High-grade squamous intraepithelial lesion prevalence was similar during first HPV detections (2.9%) and redetection (3.2%).

CONCLUSIONS

Our findings suggest many HPV redetections were likely reactivations of latent recurring infections.

Optimal Control and Cost-Effectiveness Analysis of an HPV-Chlamydia trachomatis Co-infection Model

In this work, a co-infection model for human papillomavirus (HPV) and Chlamydia trachomatis with cost-effectiveness optimal control analysis is developed and analyzed. The disease-free equilibrium of the co-infection model is shown not to be globally asymptotically stable, when the associated reproduction number is less unity. It is proven that the model undergoes the phenomenon of backward bifurcation when the associated reproduction number is less than unity. It is also shown that HPV re-infection ([Formula: see text]) induced the phenomenon of backward bifurcation. Numerical simulations of the optimal control model showed that: (i) focusing on HPV intervention strategy alone (HPV prevention and screening), in the absence of C. trachomatis control, leads to a positive population level impact on the total number of individuals singly infected with C. trachomatis, (ii) Concentrating on C. trachomatis intervention controls alone (C. trachomatis prevention and treatment), in the absence of HPV intervention strategies, a positive population level impact is observed on the total number of individuals singly infected with HPV. Moreover, the strategy that combines and implements HPV and C. trachomatis prevention controls is the most cost-effective of all the control strategies in combating the co-infections of HPV and C. trachomatis.

Considerations for Child Cancer Survivors and Immunocompromised Children to Prevent Secondary HPV-associated Cancers

Survivors of childhood cancer and other immunocompromised children are at high risk for the development of secondary human papillomavirus (HPV)-associated cancers. In this overview, the authors examine the epidemiology of vaccine efficacy, the natural history of HPV infections, and accelerated HPV-associated cancer development in these populations. The authors highlight the opportunities for preventive care and future research directives.

Epidemiological Characteristics of Human Papillomavirus (HPV) Infection in Different Groups of Women in Chongqing, China

Persistent high-risk (HR) human papillomavirus (HPV) infection is an essential risk factor for cervical carcinoma and precancerous lesion. There are differences in HPV distribution among different countries, regions and ethnic groups. The aim of this research was to reveal the epidemiological characteristics of HPV in Chongqing, China. In this study, 13,788 women aged 18 to 78 were screened for 23 HPV genotypes by PCR-reverse dot blot hybridization. The total HPV-positive rate was 19.9% (2,745/13,788), while the positive rates for HR, and low-risk (LR) HPV were 17.3% (2,379/13,788), and 4.6% (638/13,788), respectively. In addition to cervical cancer (CC) and cervical intraepithelial neoplasia (CIN) patients, the HPV infection rates among infertile women and women with gynecological diseases were markedly higher than that among healthy women. The HPV and HR-HPV infection rates in the different age groups showed statistically significant differences, and the prevalence peaks were observed in women under 20 years and over 50 years of age. Overall, HPV-52, HPV-16 and HPV-58 ranked as the top 3 most common subtypes among women in Chongqing. The results of this research provide epidemiological information regarding HPV infection in Chongqing. These data constitute valuable evidence for the prevention and management of cervical carcinoma and development of HPV vaccines.

Chlamydia Trachomatis and Human Papillomavirus Serostatus in Puerto Rican Women

OBJECTIVE

There is a high prevalence of human papillomavirus (HPV) infection in Puerto Rico, but little is known about the prevalence of Chlamydia trachomatis (CT) infection in healthy Puerto Rican women. Thus we aimed to evaluate the seroprevalence and association and the association between HPV and CT.

METHODS

This was a secondary data analysis from a cross-sectional, populationbased, study of HPV infection in women aged 16-64 years in Puerto Rico (2010-2013). Enzyme-linked immunosorbent assays (ELISA) were used to detect serum antibodies to CT and HPV. Logistic regression models were used to estimate the odds ratio (OR) for the association between HPV and CT serostatus.

RESULTS

The study included 524 women; mean age was 42 years. Overall, 97 (18.5%) women were CT-seropositive, 251 (47.0%) were HPV seropositive, and 57 (10.9%) had antibodies for both CT and HPV. Women who were CT-seropositive were more likely (p<0.05) to also be seropositive to any HPV type (ORadjusted: 1.7, IC 95% =1.1, 2.6), HPV 16/18 (ORadjusted: 1.6, IC 95% =1.0, 2.6) and HPV 6/11 (ORadjusted: 1.6, IC 95% =1.1, 2.6) than those CT-seronegative, after adjusting for possible confounding factors.

CONCLUSION

Given the association between CT and HPV seropositivity, longitudinal studies to evaluate whether CT infection influences HPV incidence and persistence in this group are warranted.

The bioinformatics analyses reveal novel antigen epitopes in major outer membrane protein of Chlamydia trachomatis

PURPOSE

The aim of this study was to predict the T-cell and B-cell epitopes in major outer membrane protein (MOMP) of Chlamydia trachomatis (CT) by using online software and also to analyse the secondary structure of MOMP through bioinformatics tools.

MATERIALS AND METHODS

The predictions of secondary structure of MOMP protein were carried out using SOPMA software, and the prediction of B-cell epitopes in MOMP protein was carried out using IEDB and LEPS software, while the T-cell epitopes were predicted by the software of IEBD and SYFPEITHI. The predictions from the software were combined with MOMP protein characteristics, including surface features, hydrophilicity, flexibility, accessibility and plasticity, to analyse the common epitope areas' response by T-cells and B-cells.

RESULTS

In the secondary structure of CT MOMP, the alpha-helices accounted for 41.62% of total amino acid, while the beta sheets and random coil accounted for 19.80% and 32.49%, respectively. Predictions combined with MOMP protein surface features, hydrophilicity, flexibility, accessibility and plasticity were further characterised, and three high-score B-cell epitope areas were found as located in 24-31, 307-311 and 318-327 amino acids of MOMP protein, respectively; in the meanwhile, three high-score T-cell epitope areas were found in 234-236, 323-329 and 338-343 amino acids of MOMP using major histocompatibility complex (MHC) class I HLA-A 0201 restrictive T-cell epitope analyser.

CONCLUSION

We established the methods by using the biological information network technologies for looking the T-cell antigen epitopes and B-cell antigen epitopes in MOMP of CT, and three novel T-cell epitopes as well as three novel B-cell epitopes were identified in the current study. It provides important information for further studying the antigenicity of CT MOMP protein and also provides useful information for developing highly efficient subunit vaccines for CT.

Epidemiology of cervical human papillomavirus (HPV) infection and squamous intraepithelial lesions (SIL) among a cohort of HIV-infected and uninfected Ghanaian women

Background

There is limited data in Ghana on the epidemiology of HPV and cervical neoplasia and their associations with HIV. This study aimed to compare among HIV-1 seropositive and HIV-seronegative Ghanaian women: (1) the prevalence, genotype distribution and risk factors associated with cervical HPV infection; and (2) the prevalence and risk factors associated with abnormal cervical cytology.

Methods

A comparative frequency-matched study was conducted in a systematic sample of women aged ≥18 years attending HIV and general outpatient clinics in Cape Coast Teaching Hospital, Ghana. Participants were interviewed and cervical samples collected for HPV genotyping (Seegene Anyplex-II HPV28) and cytological testing.

Results

Overall, 333 women were recruited, 163 HIV-1 seropositive and 170 HIV-seronegative women of mean age 43.8 years (SD ±9.4)) and 44.3 years (SD ±12.8), respectively. The prevalence of 14 high-risk (hr) HPV genotypes was higher among HIV-1 seropositive women (65.6% vs. 30.2%, P < 0.0001), as was proportion with multiple hr.-HPV infections (60.6% vs. 21.3%, P < 0.0001). HPV35 was the most prevalent hr.-HPV genotype in both groups (11.9% and 5.3%). The main factors associated with hr.-HPV infection were age for HIV-positive women and circumcision status of main sexual partner for both HIV-negative and positive women.

Abnormal cervical cytology prevalence was higher among HIV-1 seropositive women (any SIL: 14.1% vs. 1.2%, P < 0.0001; low-grade SIL [LSIL]: 4.9% vs. 0.6%, P = 0.02; high-grade SIL: 1.8% vs. 0%, P = 0.07). Among HIV-1 seropositive women, number of pregnancies and CD4+ cell count were associated with LSIL+ cytology. There was strong association between LSIL+ abnormalities and HPV35 (aOR = 4.7, 95%CI: 1.3–17.7, P = 0.02).

Conclusions

HIV-1 infected women bear significant burden of HPV infection and related disease. Prevention and screening programmes should be specifically deployed for this population in Ghana.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3682-x) contains supplementary material, which is available to authorized users.

Prognostic value of the pretreatment neutrophil-to-lymphocyte ratio in cervical cancer: a meta-analysis and systematic review

The prognostic value of pretreatment neutrophil-to-lymphocyte ratio (NLR) in cervical cancer remains controversial. We conducted a meta-analysis based on the data from 13 studies with 3729 patients to evaluate the association between the pretreatment NLR and the clinical outcomes of overall survival and progression-free survival in patients with cervical cancer. The relationship between NLR and clinicopathological parameters was also assessed. Hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) was used as the effect size estimate. Our analysis indicated that elevated pretreatment NLR was a poor prognostic marker for patients with cervical cancer because it predicted unfavorable overall survival (HR = 1.375, 95% CI: 1.200–1.576) and progression-free survival (HR = 1.646, 95% CI: 1.313–2.065). Increased NLR is also significantly associated with the larger tumor size (OR = 1.780, 95% CI: 1.090–2.908), advanced clinical stage (OR = 2.443, 95% CI: 1.730–3.451), and positive lymph node metastasis (OR = 2.380, 95% CI: 1.775–3.190). By these results, high pretreatment NLR predicted a shorter survival period for patients with cervical cancer, and it could be served as a novel index of prognostic evaluation in patients with cervical cancer.

Mechanistic mathematical models: An underused platform for HPV research

Health economic modeling has become an invaluable methodology for the design and evaluation of clinical and public health interventions against the human papillomavirus (HPV) and associated diseases. At the same time, relatively little attention has been paid to a different yet complementary class of models, namely that of mechanistic mathematical models. The primary focus of mechanistic mathematical models is to better understand the intricate biologic mechanisms and dynamics of disease. Inspired by a long and successful history of mechanistic modeling in other biomedical fields, we highlight several areas of HPV research where mechanistic models have the potential to advance the field. We argue that by building quantitative bridges between biologic mechanism and population level data, mechanistic mathematical models provide a unique platform to enable collaborations between experimentalists who collect data at different physical scales of the HPV infection process. Through such collaborations, mechanistic mathematical models can accelerate and enhance the investigation of HPV and related diseases.

Frequency of Chlamydia trachomatis infection in cervical intraepithelial lesions and the status of cytological p16/Ki-67 dual-staining

Background

Chlamydia trachomatis (Ct) is not a disease subject to mandatory reporting in Brazil, and the prevalence rate of this genital infection varies according to the region in which studies are conducted, as well as by the detection technique employed. Ct has been associated with persistence of Human papillomavirus (HPV) infection and the facilitation of cervical carcinoma development. We evaluated the Chlamydia trachomatis infection and its association with cytology, p16/Ki-67 dual-stained cytology and cervical intraepithelial lesions status in a screening cohort in Brazil.

Methods

This was a cross-sectional study of 1481 cervical samples from asymptomatic women aged 18 to 64. Samples were collected for liquid-based cytology and Ct detection by polymerase chain reaction. p16/Ki-67 double staining was performed on samples with abnormal cytology. Statistical analysis was by chi-square and likelihood-ratio tests. Odds ratio (OR) and 95% confidence intervals (95% CI) were determined.

Results

The frequency of Ct was 15.6% and its presence was not associated with detection of p16/Ki-67 [OR = 1.35 (0.5–3.4)]. There was also no association between abnormal cervical cytology and Ct-positivity [OR = 1.21 (0.46–3.2)]. Associations were observed between p16/Ki-67 and high-grade lesions detected by cytology and in biopsies [OR = 3.55 (1.50–8.42) and OR = 19.00 (0.6–7.2), respectively].

Conclusions

The asymptomatic women in our study had a high frequency of Ct infection but this was not associated with p16/Ki-67 detection in samples with abnormal cytology. The expression of p16/Ki-67 was highest in women with high-grade CIN (p = 0.003).

Prevalence and factors associated with coinfection of human papillomavirus and Chlamydia trachomatis in adolescents and young women

BACKGROUND

Human papillomavirus and Chlamydia trachomatis share the same route of sexual transmission and possess similar risk factors, indicating that coinfection may act synergistically in the induction of epithelial cell abnormalities.

OBJECTIVE

This study aimed to determine the prevalence of human papillomavirus and Chlamydia trachomatis in adolescents and young women and identify factors associated with coinfection.

STUDY DESIGN

This cross-sectional study included 276 female participants, aged 15-24 years, who were sexually active. Interviews were conducted and cervical specimens were collected for cervical smears and molecular tests. All cervical specimens were tested for 27 human papillomavirus genotypes by polymerase chain reaction amplification and hybridization to a human papillomavirus linear array. Detection of Chlamydia trachomatis was performed by polymerase chain reaction using primers directed to the region encoding the cryptic plasmid. Bivariate and multivariate analyses were performed to evaluate the factors associated with coinfection with human papillomavirus and Chlamydia trachomatis. The odds ratio, the adjusted odds ratio, and the 95% confidence interval were calculated.

RESULTS

The prevalence of infection by Chlamydia trachomatis and human papillomavirus was 9.1% (95% confidence interval, 5.61-12.4) and 47.1% (95% confidence interval, 41.0-53.2), respectively. The prevalence of coinfection with human papillomavirus and Chlamydia trachomatis was 5.8% (95% confidence interval, 3.3-9.2); coinfection with 1 human papillomavirus type was 3.3% (95% confidence interval, 1.5-6.1) and with multiple types was 2.5% (95% confidence interval, 1.0-5.2). The prevalence of cytological abnormalities was 12.3% (95% confidence interval, 8.6-16.79). Human papillomavirus infections of high oncogenic risk were more prevalent (85.4%). Factors independently associated with coinfection of human papillomavirus/Chlamydia trachomatis obtained by multivariate analysis were the initiation of sexual activity under 16 years of age with an an odds ratio of 4.9 (95% confidence interval, 1.0-23.63; P = .05) and cytological abnormalities with an odds ratio of 10.7 (95% confidence interval, 1.9-59.5; P = .01), which indicates there is risk for the detection of cytological abnormalities in adolescents and young women coinfected with human papillomavirus/Chlamydia trachomatis.

CONCLUSION

The prevalence of coinfection among our study population was of a magnitude that warrants attention by public health services. Adolescents and young women should be monitored for Chlamydia trachomatis infection and vaccinated against human papillomavirus. The association between cytological abnormalities and coinfection with human papillomavirus and Chlamydia trachomatis indicates the potential synergistic role of these infections in carcinogenesis of the cervix.

The Role of Chlamydia trachomatis in High-Risk Human Papillomavirus Persistence Among Female Sex Workers in Nairobi, Kenya

BACKGROUND

Little is known about risk factors for persistent high-risk human papillomavirus (hrHPV) infection in low-income settings, and prior research has not quantified the relative duration of hrHPV infections stratified by risk factors. We compared the duration of hrHPV infection among female sex workers (FSWs) by exposure to sexually transmitted infections (STIs), using a highly sensitive biomarker assay.

METHODS

From 2009 to 2011, 350 FSWs enrolled in this longitudinal study. Every 3 months, sociodemographic and sexual behavior data were collected via questionnaire, and APTIMA assays were used to detect the rRNA of Chlamydia trachomatis (CT), Neisseria gonorrhea, Trichomonas vaginalis, Mycoplasma genitalium, and messenger RNA of the E6/E7 oncoproteins expressed by hrHPV. Among 173 FSW who were infected with hrHPV during the observation period, accelerated failure time models estimated time ratios (TRs) for duration of hrHPV infection, comparing FSW infected with STIs at baseline to STI-uninfected FSWs.

RESULTS

Median follow-up time was 26.2 months (interquartile range, 18.8-27.5 months). The median duration of hrHPV infection among all FSWs was 9.3 months (95% confidence interval [CI], 9.3-11.5). The duration of hrHPV infection among FSW infected with CT at baseline was greater than that among FSWs who were uninfected (adjusted TR, 1.7; 95% CI, 1.2-2.6). Among FSWs who were coinfected with hrHPV and CT at baseline, the adjusted TR was 3.4 (95% CI, 2.5-5.4) compared with FSWs infected with hrHPV only. No other STI was associated with hrHPV duration.

CONCLUSIONS

Recent or concurrent CT infection was associated with prolonged hrHPV infection among a cohort of Nairobi FSWs. Management of CT could reduce risk for hrHPV persistence.

Elevated Expression of Human Papillomavirus-16/18 E6 Oncoprotein Associates with Persistence of Viral Infection: A 3-Year Prospective Study in China

BACKGROUND

An association between high-risk human papillomavirus (HR-HPV) oncoprotein expression and viral persistence has been suggested by the outcome of etiology studies, but there are no epidemiologic studies evaluating that link.

METHODS

We performed a 3-year prospective study in which 2,498 Chinese women ages 25 to 65 years were screened by six screening tests, including the Onco E6: Cervical Test (Arbor Vita Corporation) in 2011 (baseline). Six-hundred and ninety women who were positive for any of the tests and a random sample of 164 women with all negative results received colposcopy, and cervical specimens for the cobas 4800 HPV test ("cobas," Roche Molecular Systems) were collected before colposcopy; of this group, 737 cervical specimens were collected to perform cobas and Onco E6: Cervical Test in 2014 (follow-up). Twenty-four cases of HPV16/18 E6 positives and 204 selected controls at baseline, 13 cases of HPV16/18 E6 positive and another 204 selected controls at follow-up were analyzed separately using unconditional logistical regression models to estimate ORs and 95% confidence intervals (CI).

RESULTS

Compared with women who were HPV16 E6 oncoprotein negative at baseline, women in the E6-positive group had a much higher risk of HPV persistence (adjusted OR, 54.64; 95% CI, 7.19-415.09) at 3-year follow-up; a statistically strong association was also found between HPV16/18 HPV persistence and E6 oncoprotein expression detected at follow-up (adjusted OR, 360.57; 95% CI, 28.30-4,593.55).

CONCLUSIONS

A single detection of HPV16/18 E6 oncoprotein expression was strongly associated with viral persistence.

IMPACT

HPV16/18 E6 oncoprotein constitutes a marker for risk of HPV persistence. Cancer Epidemiol Biomarkers Prev; 25(7); 1167-74. ©2016 AACR.

Cervical Microbiome and Cytokine Profile at Various Stages of Cervical Cancer: A Pilot Study

Cervical cancer (CC) is caused by high-risk human papillomavirus persistence due to the immunosuppressive tumor microenvironment mediated by cytokines. Vaginal microbiota determines the presence of certain cytokines locally. We assessed the association between cervical microbiota diversity and the histopathological diagnosis of each stage of CC, and we evaluated mRNA cervical expression levels of IL-4, IL-6, IL-10, TGF-β1, TNF-α and IFN-γ across the histopathological diagnosis and specific bacterial clusters. We determined the cervical microbiota by high throughput sequencing of 16S rDNA amplicons and classified it in community state types (CST). Mean difference analyses between alpha-diversity and histopathological diagnosis were carried out, as well as a β-diversity analysis within the histological diagnosis. Cervical cytokine mRNA expression was analyzed across the CSTs and the histopathological diagnoses. We found a significant difference in microbiota's diversity in NCL-HPV negative women vs those with squamous intraepithelial lesions (SIL) and CC(p = 0.006, p = 0.036).When β-diversity was evaluated, the CC samples showed the highest variation within groups (p<0.0006) and the largest distance compared to NCL-HPV negative ones (p<0.00001). The predominant bacteria in women with normal cytology were L. crispatus and L. iners, whereas for SIL, it was Sneathia spp. and for CC, Fusobacterium spp. We found higher median cervical levels of IL-4 and TGF-β1 mRNA in the CST dominated by Fusobacterium spp. These results suggest that the cervical microbiota may be implicated in cervical cancer pathology. Further cohort studies are needed to validate these findings.

HPV genotypes distribution in Chlamydia trachomatis co-infection in a large cohort of women from north-east Italy

Human papillomavirus (HPV) and Chlamydia trachomatis are pathogens with oncogenic potential associated with persistent infections. Epidemiological data on C. trachomatis infection status, C. trachomatis/HPV co-infection and the relationship between HPV genotypes in Italian women are only preliminary. The aim of the present study was to characterize the relationship between HPV genotypes and C. trachomatis in an extending cohort of asymptomatic immunocompetent women from an area of north-east Italy. A retrospective study was conducted using Luminex technology on cervical swabs from asymptomatic immunocompetent women, comprising 921 attending the prevention centre for the Cervical Cancer Program and 6214 who had been referred to the Sexually Transmitted Infections Center, with clinical indications of HPV and C. trachomatis infections. A quantitative real-time PCR was performed to assess chronic C. trachomatis infection by heat-shock protein 60 (Hsp60) gene expression. The overall prevalence of the investigated pathogens was 39 % (359/921) for HPV and 4 % (251/6214) for C. trachomatis. The Hsp60 gene was detected in 57 % of the women infected with C. trachomatis. HPV co-infection was present in 58 % of C. trachomatis-infected women. A high prevalence of co-infection was found in women with chronic C. trachomatis infection (68 %, P = 0.0002), especially in women ≤ 25 years (72 %) where HPV multiple infections were found in 78 % (P = 0.022). HPV genotype distribution showed that uncommon low-risk genotypes were associated with C. trachomatis. These results indicate a high frequency of co-detection of multiple HPV genotypes in chronically infected young women and suggest that the expression of the C. trachomatis Hsp60 gene may favour HPV infection.

Episodic detection of human papillomavirus within a longitudinal cohort of young women

Redetection of a type-specific human papillomavirus (HPV) infection may represent reinfection. However, a growing body of literature suggests that reactivation of HPV is common and that episodic detection of a HPV infection may represent reactivation of a persistent virus. A cohort of prospectively followed adolescent women (N = 150), ages 14-17, was observed on average 6.4 years. The authors describe the redetection of 37 HPV types and associated factors of redetection of high-risk (HR) and low-risk (LR) types using Cox proportional hazard models. Of 1,248 HPV type-specific infections, 286 (22.9%) were associated with redetection after apparent clearance. Chlamydia infections (HR = 1.99 [95%CI, 1.15-3.49]) and non-condom use (HR = 1.1 [95%CI, 1.04-1.99]) were associated with increased redetection of HR-HPV infections. Oral contraceptive pills (HR = 2.73 [95%CI, 1.52-4.90]) and number of sexual partners (HR = 1.44 [95%CI, 1.04-1.99]) were associated with increased redetection of LR-HPV infections. Episodic detection of HPV is common for HR- and LR-HPV types. This finding and identified factors or redetection have clinical implications and enhances the understanding of HPV natural history.

Prevalence of sexually transmitted pathogens associated with HPV infection in cervical samples in a Mexican population

Cervical cancer development has been mainly associated with persistent human papillomavirus (HPV) infections. However, HPV infection is unlikely to be sufficient to cause cervical cancer, and the contribution of other sexually transmitted infections (STIs) could be the determining factor for cervical lesion-progression. The aim of this study was to estimate the prevalence of STIs associated with HPV-positivity in 201 cervical samples from patients who underwent annual routine gynecological exams. The overall prevalence of STIs was 57.7%, and the most frequent infection was Ureaplasma spp (UP) (39.8%), followed by Gardnerella vaginalis (GV) (25.9%), α-HPV (18.4%), Chlamydia trachomatis (CT) (1.5%), and Mycoplasma genitalium (MG) (0.5%). The highest prevalence rate of multiple non-HPV infections was observed for the age-range 31-40; for papillomavirus infection, the age-range was 21-30. In normal cervical samples, HPV16 was the most prevalent genotype (24.3%), followed by genotypes 58 (13.5%) and 52 (10.8%). Intriguingly, HPV18 was not detected in the study population, and genotypes 52 and 58 were found exclusively in samples with abnormal cytology. Papillomavirus infection with oncogenic types was significantly associated with GV (P = 0.025) and strongly associated with multiple non-HPV pathogens (P = 0.002). The following variables correlated significantly with cytological diagnosis of low-grade squamous intraepithelial lesion (LSIL): GV (P = 0.028), multiple non-HPV infections (P = 0.001), and high-risk HPV positivity (P = 0.001). Epidemiological data from this study will contribute to the molecular detection of sexually transmitted pathogens from screening programs to identify those women who are at risk for developing cervical lesions.

Lack of significant effects of Chlamydia trachomatis infection on cervical cancer risk in a nested case-control study in North-East Thailand

Cervical cancer continues to be an important public health problem in Thailand. While the high risk human papillomavirus (HPV) types have been established as the principle causative agent of both malignancies and the precursor lesions, cervical intraepithelial neoplasia (CIN), other factors may also be involved like other sexually transmitted diseases, as well as smoking. Chlamydia trachomatis is an obligate intracellular Gram-negative bacterium which has a tendency to cause chronic infection featuring inflammation and therefore might be expected to increase the risk of cervical cancer. In the present nested case-control study, 61 cases of cervical cancer and 288 matched controls with original serum samples were identified from the Khon Kaen Cohort, established in the North-East of Thailand, by linkage to the Khon Kaen population based cancer registry. C. trachomatis specific IgG antibodies at recruitment were measured by microimmunofluorescence and assessed for association with cervical cancer using STATA release10. No significant link was noted either with all cancers or after removal of adenocarcinomas. The results suggest no association between Chlamydia infection and cervical cancer development in North-East Thailand, but possible influencing factors must be considered in any future research on this topic.

High prevalence of hpv multiple genotypes in women with persistent chlamydia trachomatis infection

BACKGROUND

Chlamydia trachomatis interaction with HR-HPV types has highlighted a central role in cervical cancer development. The aim of this study was to investigate HPV prevalence and genotypes distribution in women at risk for C. trachomatis infection and negative for intraepithelial lesion or malignancy.

METHODS

1071 cervical swabs were tested for C. trachomatis by Real Time PCR and genotyping by ompA gene sequencing. Additionally, a quantitative Real time-PCR was performed to assess the expression of the C. trachomatis Hsp60-encoding gene (Ct604 portion), linked to a persistent status of infection. HPV infection and genotypes was investigated in C. trachomatis positive women using Luminex technology.

RESULTS

C. trachomatis infection was detected in 53 out of 1071 (4.5%) samples, of which the 53% resulted positive for Hsp60 gene expression. The overall prevalence of HPV infection in C. trachomatis positive samples was of 60.4% (32/53): in 37.5% of samples was present a single genotype, while multiple genotypes infections were found in the 62.5% of them. Among women with a C. trachomatis chronic infection, 68% were HPV co-infected and the 79% showed multiple genotypes. Should be noted that levels of C. trachomatis Hsp60 expression in HPV co-infected women were significantly lower compared to women infected only with C. trachomatis. The C. trachomatis serotype F was found in the majority of samples, independently of HPV infection.

CONCLUSIONS

A high prevalence of HPV multiple infections have been found in young women affected with a C. trachomatis chronic infection. These observations suggested that the expression of CHSP60-1, interfering with both apoptotic and cellular senescence pathways, may promote a favourable local microenvironment for HPV infection.

HPV and Chlamydia trachomatis co-detection in young asymptomatic women from high incidence area for cervical cancer

Chlamydia trachomatis causing chronic inflammatory diseases has investigated as possible human papillomavirus (HPV) cofactor in cervical cancer. The aim of this study is to evaluate the prevalence of Chlamydia trachomatis and HPV co-infection in different cohorts of asymptomatic women from a Northern Italy area at high incidence for cervical cancer. Cervical samples from 441 females were collected from Cervical Cancer Screening Program, Sexually Transmitted Infectious and Assisted Reproductive Technology centres. HPV and Chlamydia trachomatis were detected simultaneously and genotyped using a highly sensitive bead based assay. The overall prevalence of Chlamydia trachomatis was estimated 9.7%, in contrast with the reported national data of 2.3%, and co-infection with HPV was diagnosed in the 17% of the samples. In females ≤ 25 years of age, the infection reached a peak of 22% and co-infection with HPV of 45.8% (P < 0.001). Of note, in young females diagnosed with low grade cervical lesions, no significant difference between Chlamydia trachomatis and HPV distribution was observed, while differently, HPV co-infection was found significantly associated to the presence of intraepithelial lesions when compared to older females (20% vs. 1%; P < 0.001). In this study, the use of a high sensitive molecular technique exhibited higher analytical sensitivity than the referred assays for the diagnosis of Chlamydia trachomatis and HPV co-infection in asymptomatic females, leading to reduction of the potential to identify incorrectly the infection status. An active screening for timely treatment of Chlamydia trachomatis infection is suggested in young females to evaluate a possible decrease in incidence of pre-cancer intraepithelial lesions.