Prevalence of Chlamydia infection among women visiting a gynaecology outpatient department: evaluation of an in-house PCR assay for detection of Chlamydia trachomatis

Low-cost conventional PCR techniques enable simultaneous detection of bacterial sexually transmitted infections with enhanced sensitivity and specificity

PURPOSE

Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Mycoplasma hominis (MH), the three most common treatable bacterial sexually transmitted infections (STIs) worldwide can lead to many complications if remain untreated. Screening of high-risk population with highly sensitive methods will lead to significant improvement in patient outcomes and will prevent downward transmission. The advantages of Polymerase chain reaction (PCR) based assay are not only high sensitivity and specificity, but also detection of multiple organisms in a single reaction which reduce the result turn-around time. The aim of the present study was to evaluate the feasibility of a multiplex PCR assay method targeting 16S rRNA gene for simultaneous detection of NG, CT and MH infection along with their trend and occurrence among high-risk population in Assam, Northeast India.

METHODS

A cross-sectional study was undertaken, where a total of 200 randomly selected patients from high-risk population were included. After validation of singleplex PCR, Multiplex PCR (M-PCR) was performed along with the traditional culture method for NG.

RESULTS & CONCLUSION

The overall agreement of M-PCR with singleplex PCR was very high (100%). The occurrence of STI was found to be very high (101/200; 50.5%). Furthermore, co-infection was detected in 10/200; 5%) individuals. Infection was more common among young individuals (p < 0.05) and males out-numbered females (p < 0.05). The most common organism detected was CT (42/200; 21%) followed by NG (41/200; 20.5%) and MH (20/200; 10%). The M-PCR assay workflow is simple, cost effective and can be used in routine diagnostic laboratories with basic molecular facilities.

Prevalence of human papilloma virus and Chlamydia trachomatis in endometrial and cervical carcinoma: a comparative study in North Indian women

Cervical cancer (Cacx) is the second and endometrial cancer (Ec) is the third most common gynecological cancer worldwide. The present study aims to understand the complex and unexplored conditions occurring in cervix and endometrium of the female genital tract caused due to the infection of the human papilloma viruses (HPVs) and Chlamydia trachomatis (CT). A total of 300 tissue biopsy samples of cervix and endometrium were included in the present study and tested for the presence of HPV and CT deoxyribonucleic acid (DNA) by using polymerase chain reaction (PCR) technique. The odds ratios and 95% confidence interval were considered for the calculation of the association of HPV and CT infection with the risk of cervical or Ec. Among endometrial patients, samples were 5% positive for HPV and 5% positive for CT infection. Among endometrial control group, no sample was found positive for either HPV or CT infection. Among cervical patients, 72% samples were positive for only HPV infection and 1% samples were positive for only CT infection. Among control group, 7% of samples were positive for only HPV infection and 3% were positive for only CT infection. The co-infection of CT with HPV in 9% of Cacx cases and in 2% of cervical control samples was also observed. This is the first study in Indian women to detect the prevalence of HPV and CT infections in endometrium cases and control. An updated estimate regarding the HPV and CT prevalence in cervix cases and control samples was also provided.

Aftermath of Chlamydia Trachomatis - The Tip of an Iceberg in Female Reproductive Health

OBJECTIVE

The magnitude of infertile couples worldwide was found to be 60-80 million. Genital infection due to Chlamydia trachomatis (C. trachomatis) is one of the most prevalent sexually transmitted infections (STIs) which may present as PID, leading to ectopic pregnancy, infertility or other adverse health outcomes. This study was done to assess the prevalence of C. trachomatis infections among female patients with infertility using real time PCR (RT-PCR) and to compare the findings of molecular testing with hysterosalpingography (HSG) and ultrasonography (USG).

MATERIAL AND METHODS

50 endocervical swabs were collected from women of reproductive age group attending infertility clinic and stored at -80 ºC. DNA extraction was done with Helini bacterial mini spin kit and tested for C. trachomatis DNA by RT-PCR kit.

RESULTS

Of the 50 patients, 43 (86%) had primary infertility, and 7 (14%) had secondary infertility. Three (6%) were positive for C. trachomatis by RT-PCR. Two had primary infertility and one had secondary infertility.

CONCLUSION

Routine screening of C. trachomatis even in high-risk populations is not available in developing countries like India. The World Health Organization recommends syndromic approach for case management. Hence, a cost-effective, highly sensitive and specific test is the pressing priority in resource poor settings.

Multilocus VNTR analysis-ompA typing of Chlamydia trachomatis isolates in Tehran, Iran

INTRODUCTION

This study is the first to describe the genetic diversity of C. trachomatis strains derived from patients with signs and symptoms of genitourinary infections admitted to Tehran health centers and hospitals using the high-resolution genotyping method, multilocus variable-number tandem-repeat analysis with ompA sequencing (MLVA)-ompA.

METHODS

One hundred and sixty-seven urogenital specimens were collected from October 2019 to July 2020. Specimens were inoculated to cell culture and examined for the presence of C. trachomatis isolates by microscopic valuation. Out of 167 samples, 19 (11.3%) viable C. trachomatis organisms were isolated in cell culture. Eighteen isolates were successfully genotyped by MLVA-ompA analysis.

RESULTS

The most prevalent ompA genotypes were E, D, F and G, comprising 42%, 26.3% and 21% and 10.5% of isolates, respectively. Other genotypes were not detected from any of the samples. Out of the 18 fully genotyped isolates, 10 different MLVA-ompA genotypes were obtained. The most prevalent MLVA-ompA genotypes were 8.6.1-E (33.3%) and 8.5.2-D (16.6%). Genotype 8.6.1-E was common in both females and males.

CONCLUSIONS

Our results showed that MLVA-ompA analysis was more discriminatory than ompA typing alone and, therefore, a suitable complement to ompA. Using this method, dominant genotypes in the community and transmission patterns in sexual networks could be identified. The high diversity of C. trachomatis strains in Tehran may be due to the low level of public health and awareness, and future studies are needed.

Cross-Sectional Analysis of Human Papillomavirus Infection and Cytological Abnormalities in Brazilian Women

The aim of this study was to determine the incidence of infections and cytological abnormalities and to investigate possible predisposing factors such as sociodemographic characteristics, sexual behavioral habits, and gynecological and obstetric backgrounds. Between 2013 and December 2016, a cross-sectional study was conducted among 429 consenting women, from whom cervical samples were tested for the presence of Human papillomavirus (HPV) by polymerase chain reaction (PCR). Susceptibility to HPV infection was assessed by binary logistic regression in light of possible predisposing factors, which were collected using a questionnaire. In our sample population, the prevalence of HPV infection was 49%; high-risk types had a higher prevalence of 89.1%. A larger proportion of HPV-infected women were under 25 years of age, were single, and had monthly incomes up to minimum wage. Multivariate binary logistic regression analysis showed that age younger than 25 years increased the odds of infection fivefold, while a monthly income of one to three minimum wages provided protection against HPV infection, even if the women were married or had a cohabiting partner. In the HPV-positive group, squamous intraepithelial lesions (SIL) occurred more frequently in women who earned up to one minimum wage monthly, but a monthly income of one to three minimum wages protected against the development of SIL. The results suggest that age, marital status, and monthly income are important cofactors for HPV infection and the development of SIL.

Multiple sexually transmitted co-infections are associated with adverse reproductive outcomes in asymptomatic adolescent pregnant women; A Prospective cohort study

Background

A prospective cohort was conducted to assess the prevalence of seven RTIs/STIs in adolescent asymptomatic pregnant women to find a significant correlation between infection and pregnancy.

Methods

The study was restricted to 18–19 years of asymptomatic adolescent pregnant women attending Ante-Natal Care and the health status of the pregnant women were followed up to parturition. The health status of the infant was followed till 6 months post-delivery. The prevalence of the concerning pathogens and the significance of their association with adverse outcomes of pregnancy were determined.

Results

Among 279 subjects, the most significant co-infections were observed for M. hominis with U. parvum (9.31%; p-value–0.0071/OR−2.6421) and U. urealyticum (7.88%; p-value–0.0119/OR−2.6455). Statistically significant associations were found between C. trachomatis [(p-value-0.0439); OR−2.9902] and M. genitalium [(p-value−0.0284); OR−3.442] with PTB, N. gonorrhoeae with LBW &lt;2.5 kg [(p-value−0.0052);OR−4.9017], U. urealyticum with VLBW &lt;2 kg [(p-value-0.0262);OR−3.0207], M. genitalium [(p-value-0.0184); OR−11.7976] and T. vaginalis with PROM [(p-value 0.0063); OR−19.4275] while M. genitalium [(p-value 0.0190); OR–12.9230] and U. urealyticum [(p-value 0.0063); OR-14.5149] with PPROM with 95% CI respectively.

Conclusions

Asymptomatic adolescents are at high risk of adverse pregnancy outcomes if infected with the concerned pathogens.

Improved management can be achieved by introducing additional parameters in the syndromic diagnosis of nonviral sexually transmitted infections at low-resource settings

BACKGROUND

The syndromic approach is a simple and affordable strategy for the management of sexually transmitted infections in countries with low-resource settings. However, because of the lack of specificity and accuracy, the risk of overuse and misuse of antibiotics is very high. Here, we proposed a more specific and accurate algorithm compared with the current algorithm used for syndromic case management of 3 common sexually transmitted pathogens and compared its precision with laboratory-based tests.

OBJECTIVE

This study aimed to report a comparative account of the accuracy of existing syndromic case management guidelines followed in mainstream hospitals, for taking care of patients with nonviral sexually transmitted infections, concerning an approach involving an alternative algorithm formulated in our laboratory followed by polymerase chain reaction testing.

STUDY DESIGN

This was an observational study that compared the data between 2 categories based on diagnostics accuracy and treatment. In category I, symptoms of infection were scored on the basis of the existing National AIDS Control Organization and National AIDS Control Programme guidelines, and patients were treated before testing by polymerase chain reaction. In category II, patients were recruited on the basis of the National AIDS Control Organization and National AIDS Control Programme guidelines with additional alternative syndromic case management parameters. All samples were tested by polymerase chain reaction for Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis and clinically correlated before giving the treatment.

RESULTS

In category I, among 646 women with symptomatic infection, only 46 (7.82%) tested positive by polymerase chain reaction assay for at least 1 of the pathogens, and 600 (92.87%) tested negative for infection by any of the 3 pathogens. The total estimated percentages of the overuse and misuse of antibiotics were 92.87% and 8.69%, respectively. Correct and complete treatment based on laboratory outcome compared with National AIDS Control Programme guidelines was 42 of 46 (91.30%). The estimated overuse of azithromycin and cefixime (Gray Kit) was 29.69%, the estimated overuse of a combination of doxycycline, cefixime, and metronidazole (Yellow Kit) was 29.87%, and the estimated overuse of a combination of doxycycline, cefixime, metronidazole, and azithromycin (Gray with Yellow Kit) was 11.45%. In category II, wherein patients were treated using an alternative syndromic approach and polymerase chain reaction diagnostics, 243 of 319 patients (76.15%) were infected with either of the pathogens (Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis), whereas 76 of 319 patients (23.82%) were negative for any of the 3 pathogens. Among 243 patients with infection, 99 of 243 (40.74%) were infected with a single pathogen, whereas 144 of 243 (59.20%) were coinfected. Of 144 coinfected patients, the percentage of Chlamydia trachomatis + Neisseria gonorrhoeae infection was the highest (51.38%), followed by coinfection with all 3 pathogens (30%). Coinfection with Chlamydia trachomatis + Trichomonas vaginalis was 9.72%, and coinfection with Neisseria gonorrhoeae + Trichomonas vaginalis was 9.03%. The estimated overuse of antibiotics was found to be 23.82% only.

CONCLUSION

The proposed alternative strategies of syndromic case management can reduce the percentage of misuse and overuse of antibiotics from 92.87% to 23.82%. Moreover, syndromic case management alone was insufficient for disease management.

Prevalence of Endocervical Chlamydia trachomatis Infection and Related Risk Factors Among Women Attending Gynecology Clinic of Birjand University of Medical Sciences, East of Iran

Background: Chlamydia trachomatis is one of the most common sexually transmitted infections in the world. However, there is no detailed information on its incidence, especially in developing countries where routine laboratory diagnosis is unavailable. Objectives: This study aimed to investigate the prevalence of endocervical C. trachomatis infection and related risk factors among women attending the University Gynecology Clinic of Birjand, East of Iran. Methods: This cross-sectional study was conducted on 195 women attending the University Gynecology Clinic in South Khorasan, Birjand. Endocervical sampling was performed in a lithotomy position using a sterile brush. Identification of C. trachomatis was performed by real-time PCR method using GeneProof C. trachomatis PCR kit. Data on socio-demography and potential risk factors for genital infection were analyzed using SPSS software (version 21). Results: In the study, the prevalence rate of C. trachomatis among women was reported 4.1% (8/195 subjects). Statistical analysis showed that the rate of C. trachomatis infection in women was only statistically related to the history of vaginal infection (P = 0.001). Although there was no statistically significant association between chlamydial infection and age, the highest infection rate was in women less than 30 years old. Conclusions: Given the relatively significant incidence of C. trachomatis infection among women, our findings highlight the importance of routine screening and early diagnosis of C. trachomatis to control the infection.

Detection of chlamydia trachomatis infection among the pregnant women attending a tertiary care hospital in Kerala - South India by polymerase chain reaction

Background

Chlamydia trachomatis infection is the most prevalent bacterial sexually transmitted infection and may influence pregnancy outcome.

Aims and Objectives

This study was conducted to assess Chlamydial infection during pregnancy by PCR.

Materials and Methods

Study group consists of patients who are attending the antenatal clinics. Endocervical swabs were collected from 300 patients.

Results

Off the 300 samples tested, 29 were positive as per PCR which used CT F : 5' CGT GTC GGC AAT CCT GCT GAT 3' and CT R : 5' GTC GAT AAC ATA GTC ACG ATA GTC 3'as the primers.

Conclusion

This suggests there is a prevalence of Chlamydia trachomatis in our population which is 10%. Hence, it should be noted as a significant public health problem especially among sexually active young women of child bearing age. Timely detection and prompt treatment of Chlamydial infection during pregnancy can eliminate its adverse outcomes.

Sexually Transmitted Infections and Behavioral Determinants of Sexual and Reproductive Health in the Allahabad District (India) Based on Data from the ChlamIndia Study

BACKGROUND

Sexually transmitted infections (STIs), like Chlamydia trachomatis and Neisseria gonorrhoeae (CT and NG, respectively) are linked to an important sexual and reproductive health (SRH) burden worldwide. Behavior is an important predictor for SRH, as it dictates the risk for STIs. Assessing the behavior of a population helps to assess its risk profile.

METHODS

Study participants were recruited at a gynecology outpatient department (OPD) in the Allahabad district in Uttar Pradesh India, and a questionnaire was used to assess demographics, SRH, and obstetric history. Patients provided three samples (urine, vaginal swab, and whole blood). These samples were used to identify CT and NG using PCR/NAAT and CT IgG ELISA.

RESULTS

A total of 296 women were included for testing; mean age was 29 years. No positive cases of CT and NG were observed using PCR/NAAT. A 7% (22/296) positivity rate for CT was observed using IgG ELISA. No positive association was found between serology and symptoms (vaginal discharge, abdominal pain, dysuria, and dyspareunia) or adverse pregnancy outcomes (miscarriage and stillbirth). Positive relations with CT could be observed with consumption of alcohol, illiteracy, and tenesmus (p-value 0.02-0.03).

DISCUSSION

STI prevalence in this study was low, but a high burden of SRH morbidity was observed, with a high symptomatic load. High rates of miscarriage (31%) and stillbirth (8%) were also observed among study subjects. No associations could be found between these ailments and CT infection. These rates are high even for low- and middle-income country standards.

CONCLUSION

This study puts forward high rates of SRH morbidity, and instances of adverse reproductive health outcomes are highlighted in this study, although no associations with CT infection could be found. This warrants more investigation into the causes leading to these complaints in the Indian scenario and potential biases to NAAT testing, such as consumption of over-the-counter antimicrobials.

Multiplex nested polymerase chain reaction targeting multiple genes for the detection of Neisseria gonorrhoeae and Chlamydia trachomatis in genitourinary specimens

Objectives:

The objective of this study was to design and evaluate a novel multiplex nested polymerase chain reaction (PCR) protocol for simultaneous detection of Neisseria gonorrhoeae and Chlamydia trachomatis in genitourinary specimens obtained from symptomatic patients clinically suspected of sexually transmitted infections (STIs), targeting two different genes each for these pathogens.

Materials and Methods:

A total of 116 genitourinary specimens were collected from men (n = 12) and women (n = 104). Direct microscopy, culture isolation, and antimicrobial susceptibility testing for N. gonorrhoeae were performed. Multiplex nested PCR was performed on clinical samples using novel designed primers targeting porA pseudogene and opa gene of N. gonorrhoeae and momp gene and cryptic plasmid of C. trachomatis simultaneously. DNA sequence analysis of nested PCR amplicons for each of four gene targets was carried out for the validation of in-house designed primers and PCR protocol.

Results:

A total of 51.72% (60/116) patients were detected to have either of the two STIs. About 35.35% (41/116) of patients were positive for C. trachomatis and 33.62% (39/116) for N. gonorrhoeae by employing multiplex nested PCR. Coinfection with N. gonorrhoeae and C. trachomatis was detected in 17.24% (20/116) patients. 31.5% endocervical swabs (n = 54), 64.4% speculum-assisted high vaginal swabs (n = 45), and 80% self-collected vaginal swabs (n = 5) were detected positive for either of two STIs.

Conclusions:

The multiplex nested PCR protocol designed and employed in the present study may be used in the diagnosis and management of both symptomatic as well as asymptomatic cases of N. gonorrhoeae and C. trachomatis, particularly among high-risk groups.

Multi-centric validation of an in-house-developed beacon-based PCR diagnostic assay kit for Chlamydia and Neisseria and portable fluorescence detector

OBJECTIVE

The development of an accurate, sensitive, specific, rapid, reproducible, stable-at-room-temperature and cost-effective diagnostic kit, and a low-cost portable fluorescence detector to fulfil the requirements of diagnostic facilities in developing countries.

METHODS

We developed the 'Chlamy and Ness CT/NG kit' based on molecular beacons for the detection of Chlamydia trachomatis (CT) and Neisseriagonorrhoeae (NG). Multi-centric evaluation of the CT/NG kit was performed using the commercially available nucleic acid amplification test (NAAT)-based FTD Urethritis basic kit for comparison from December 2014 to November 2016. The stability of the kit reagents at 4 and 37 ˚C and the inter-day reproducibility of results were also analysed.

RESULTS

The sensitivity and specificity of the kit were found to be 95.83 and 100.00 % for the detection of C. trachomatis and 93.24 and 99.75 % for N. gonorrhoeae, respectively, when tested against the commercial kit. The positive predictive value (PPV) was 100.00 and 98.57 %, whereas the negative predictive value (NPV) was 99.54 and 98.79 % for C. trachomatis and N. gonorrhoeae, respectively. Analysis of the kappa statistics enhanced the 'inter-rater' κ=0.976 for Chlamydia and κ=0.943 for Neisseria.

CONCLUSION

Our kit was found to be as sensitive and specific as commercially available kits. Its low cost and ease of use will make it suitable for the routine diagnosis of C. trachomatis and N. gonorrhoeae in the resource-limited settings of developing countries.

Burden of Chlamydia trachomatis in India: a systematic literature review

Chlamydia trachomatis (hereafter CT) is Gram-negative, obligate intracellular pathogen. It causes the world's most common non-viral sexually transmitted disease. India is home to the world's greatest burden of infectious diseases, yet information on prevalence rates of CT is scarce. This article systematically reviews the literature for the prevalence rates and testing methods in India. A total of 27 studies were included. Four main patients groups (symptomatic women, infertile women, pregnant women and asymptomatic population groups) could be identified with varying rates of CT (0.1%-32% using PCR, 2.4%-75% using ELISA serology). Most of the studies originated from urban settings, 11 of them from New Delhi. In-house PCR was the most common diagnostic technique used generating the following ranges in prevalence for the four group studies: symptomatic women 10%-50%, pregnant women 0.1%-2.5% and asymptomatic populations 0.9%-24.5%. The rates among infertile women were 9%-68% based on serology results. The prevalence rates featured in this paper are in line with other locations across the Indian subcontinent. This review highlights the extreme heterogeneity in the limited studies available in India on CT and the need for standardized guidelines for diagnosis and management of CT in India. The availability of resources should be considered in the formulation of recommendations.

Molecular characterization of lower vaginal swabs for Human papilloma virus in association with Chlamydia trachomatis infection in Cameroonian Women

Human papilloma virus (HPV) infection is an etiological factor for cervical cancer development and Chlamydia trachomatis (Ct) is considered as a cofactor. Understanding the dynamics of HPV and Ct infection could help to explain the incidence of early onset of cervical cancer (CC) observed in Cameroon. Lower vaginal swabs and sera from sexually active women were analyzed for HPV and Ct infection in association with risk factors. Questionnaires were used to document patients' lifestyle and risk factors. A total of 206 women participated in the study average 28.1±8years (16-50 years). HPV prevalence was 23.3% with subtypes 16 and 18 at respectively 2.9% and 1%. Ct infection totalised 40.8%, of which 23.8% were HPV- Ct co-infections. HPV infection was inversely associated with age (p=0.028). We found a positive association between Ct infection and the number of sex partners (p=0.012) and a negative association with parity (p=0.032). There was no significant association between HPV and Ct infections. High rates of HPV and Ct infections could be an indicator of cervical cancer risk in the near future. There is therefore an urgent need for sensitization as well as implementation of appropriate preventive measures.

Detection of genital chlamydial and gonococcal infection using urine samples: A community-based study from India

Sexually transmitted infections (STI) have a major impact on the reproductive health of women. Among the different etiological agents of STIs, Chlamydia trachomatis and Neisseria gonorrhoeae are the main bacterial pathogens that cause sexually transmitted infections in women. The aim of the study was to estimate the prevalence of genital chlamydial and gonococcal infection among women in the age group of 18-65 years from a community-based setting. A community-based cross-sectional study was performed using the archived urine samples (n=811) of women in the age group of 18-65 years for C. trachomatis and N. gonorrhoeae using a multiplex conventional Polymerase Chain Reaction (PCR). Out of 811 samples tested in the present study, 2 (0.24%) were tested positive for C. trachomatis and none were positive for N. gonorrhoeae. The study demonstrates the very low prevalence of C. trachomatis and N. gonorrhoeae infection in a rural community. For large population-based screening, urine samples were observed to be more socially acceptable and cost-effective.

Evaluating the utility of syndromic case management for three sexually transmitted infections in women visiting hospitals in Delhi, India

Utility of syndromic case management (SCM) in women visiting obstetrics & gynecology department needs to be evaluated as it is subjective and imperfect. Consequently, antibiotic resistance has accelerated along with increased risk of infection to the partners. To understand the effectiveness and/or inadequacies of SCM, 11000 women were recruited and examined by clinicians for infection by Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Trichomonas vaginalis (TV), Bacterial vaginosis (BV) and others. Amongst these patients, 1797 (16.3%) reported vaginal discharge (VD). Other symptoms included: vaginitis (97%), cervicitis (75%), genital ulcers (60%), abnormal vaginal discharge (55%) and lower abdominal pain (48%). The patients were treated for single or co-infections using pre-packed National Aids Control Program III STI/RTI Kits. However, based on PCR diagnostics, 1453/1797 (81%) subjects were uninfected for NG/TV/CT. Amongst 344 (19%) infected patients, 257 (75%) carried infection with single pathogen (TV/NG/CT) while 87/344 (25%) were co-infected with multiple pathogens. Prevalence of TV, NG & CT was 4%, 7% and 8% respectively. Co-infection with CT + NG was highest, 51% (44/87), whereas, co-infection with CT + TV was 21% and NG + TV was 18% while co-infection with all three pathogens was 1.3%. We conclude that SCM is imprecise and successful intervention requires accurate and confirmatory diagnostic approach.

Low-cost, real-time, continuous flow PCR system for pathogen detection

In this paper, we present a portable and low cost point-of-care (POC) PCR system for quantitative detection of pathogens. Our system is based on continuous flow PCR which maintains fixed temperatures zones and pushes the PCR solution between two heated areas allowing for faster heat transfer and as a result, a faster PCR. The PCR system is built around a 46.0 mm × 30.9 mm × 0.4 mm disposable thermoplastic chip. In order to make the single-use chip economically viable, it was manufactured by hot embossing and was designed to be compatible with roll-to-roll embossing for large scale production. The prototype instrumentation surrounding the chip includes two heaters, thermal sensors, and an optical system. The optical system allows for pathogen detection via real time fluorescence measurements. FAM probes were used as fluorescent reporters of the amplicons generated during the PCR. To demonstrate the function of the chip, two infectious bacteria targets were selected: Chlamydia trachomatis and Escherichia coli O157:H7. For both bacteria, the limit of detection of the system was determined, PCR efficiencies were calculated, and different flow velocities were tested. We have demonstrated successful detection for these two bacterial pathogens highlighting the versatility and broad utility of our portable, low-cost, and rapid PCR diagnostic device.

Prevalence of Chlamydia trachomatis among Childbearing Age Women in India: A Systematic Review

Background. Infection with Chlamydia trachomatis (CT) can lead to reproductive sequelae. Information on the general population of childbearing age women in India is sparse. We reviewed the literature on CT prevalence within the general population of reproductive aged women in order to improve the efforts of public health screening programs and interventions. Objective. To conduct a literature review to determine the prevalence of Chlamydia trachomatis among childbearing age women in India. Search Strategy. Ovid Medline and PubMed databases were searched for articles from January 1, 2003, through December 31, 2014. Search terms included "Chlamydia trachomatis", "CT", "prevalence", "India", and "sexually transmitted infections". Selection Criteria. Studies on prevalence data for CT among women of childbearing age (15-45) living in India were included. Data Collection and Analysis. Articles that met the inclusion criteria were extracted by two readers and discrepancies solved through discussion. Results. Reported prevalence of active CT infection among lower risk groups ranged from 0.1% to 1.1% and in higher risk group from 2.7% to 28.5%. Conclusion. CT prevalence among women in India is comparable to other countries. Screening programs to prevent adverse outcomes among Indian women of childbearing age and their offspring are warranted.

Comparative analysis of syndromic and PCR-based diagnostic assay reveals misdiagnosis/ overtreatment for trichomoniasis based on subjective judgment in symptomatic patients

Background

Trichomoniasis, a sexually transmitted disease (STD), is caused by Trichomonas vaginalis in both men and women. Screening of trichomoniasis is problematic in resource challenged settings as currently available, inexpensive diagnostic methods are of low sensitivity and/or specificity. In India, National AIDS Control organization (NACO) recommended syndromic case management (SCM) for treatment. The objective of the present study was to compare the utility of the NACO-NACP III Algorithms for STI/RTI treatment used by clinicians with PCR based diagnosis.

Methods

Patients visiting Department of Obstetrics & Gynecology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi from January 2011 to June 2014 were enrolled in the study to compare the diagnostic efficiency of PCR-based assays against SCM. Based on SCM, patients (n = 820) were treated with antibiotics using pre-packed STI/RTI kits (sexually transmitted infection/reproductive tract infection; procured by National AIDS Control/State AIDS Control Society (NACO/SACS), Ministry of Health and Family Welfare, Govt of India.) under National AIDS Control Programme (NACP III) for syndromic case management (SCM). Ectocervical dry swab samples were also obtained from these patients and out of that 634 samples were tested by PCR. Total genomic DNA was extracted from these samples and used as template for PCR amplification using pfoB, gyrA and orf1 gene specific primers for diagnosis of T. vaginalis (TV), Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) respectively.

Results

Out of 6000 patients who visited OPD, 820 (14 %) female patients reported vaginal discharge and were recommended antibiotic treatment for one or more pathogens namely, TV, CT, NG and Candida or for co-infection. On the basis of signs & symptoms and NACO guidelines, the following distribution of various infections was observed: TV (46 %), CT (20 %), coinfection with TV and CT (12 %), coinfection with CT and NG (11 %), coinfection with TV, CT and Candida (7 %) and coinfection with TV and NG (2 %). Others were infected with NG alone (1 %), coinfected with TV and Candida (0.4 %) and 0.3 % were coinfected with CT, NG and Candida. Based on PCR method, 110 (17 %) women tested positive for one or more of these three pathogens while 524 (83 %) women were negative for any of these three pathogens but could be positive for other STIs not tested in this study. Since all the patients (634) were given antibiotics, we estimate that the over-treatment was 85 % while 524 (83 %) patients were also misdiagnosed by SCM.

Conclusions

The over-treatment and inaccurate diagnosis of pathogens due to subjective judgment based on syndromic approach in symptomatic women is a large economic wastage and may also contribute towards increased resistance. The misdiagnosed patients will also serve as a reservoir for transmission of pathogens to their sexual partner.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0133-x) contains supplementary material, which is available to authorized users.

Diagnosis of Neisseria gonorrhoeae using molecular beacon

Neisseria gonorrhoeae is an important sexually transmitted diseases (STD) causing pathogen worldwide. Due to absence of an affordable diagnostic assay, routine screening of gonococcal infection becomes impossible in developing countries where infection rates are maximum. Treatment is given on the basis of symptoms alone which leads to spread of infection. Thus, development of a rapid, sensitive, specific, and PCR based visual diagnostic assay suitable for developing countries, required for better disease management, is aimed at in present study. Endocervical swabs were collected from patients visiting gynecology department of various hospitals in Delhi. In-house PCR based assay was developed and modified to visual assay using molecular beacon for end-point detection. It was evaluated against Roche AMPLICOR NG kit and rmp gene. Specificity of beacon was confirmed by competition experiments. Diagnostic test was 98.21% specific and 99.59% sensitive whereas negative and positive predicted value were 99.40% and 98.78%, respectively. We also observed that twice the concentration (2X) of premix was stable at 4°C for 4 months and dry swab samples gave concordant results with that of wet swabs. These features make the test best suitable for routine diagnosis of genital infections in developing countries.

Highly sensitive and novel point-of-care system, aQcare Chlamydia TRF kit for detecting Chlamydia trachomatis by using europium (Eu) (III) chelated nanoparticles

Background

The bacterium Chlamydia trachomatis is one of the leading causes of sexually transmitted diseases worldwide. Since no simple and effective tool exists to diagnose C. trachomatis infections, we evaluated a novel point-of-care (POC) test, aQcare Chlamydia TRF kit, which uses europium-chelated nanoparticles and a time-resolved fluorescence reader.

Methods

The test performance was evaluated by comparing the results obtained using the novel POC testing kit with those obtained using a nucleic acid amplification test (NAAT), using 114 NAAT-positive and 327 NAAT-negative samples.

Results

The cut-off value of the novel test was 20.8 with a detection limit of 0.27 ng/mL. No interference or cross-reactivity was observed. Diagnostic accuracy showed an overall sensitivity of 93.0% (106/114), specificity of 96.3% (315/327), positive predictive value (PPV) of 89.8% (106/118), and negative predictive value (NPV) of 97.5% (315/323). The sensitivity of the novel test was much higher than that of currently available POC tests. Furthermore, the relative ease and short turnaround time (30 min) of this assay enables C. trachomatis-infected individuals to be treated without a diagnostic delay.

Conclusions

This simple and novel test is a potential tool to screen a larger population, especially those in areas with limited resources.

Highly specific and efficient primers for in-house multiplex PCR detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum

Background

Although sophisticated methodologies are available, the use of endpoint polymerase chain reaction (PCR) to detect 16S rDNA genes remains a good approach for estimating the incidence and prevalence of specific infections and for monitoring infections. Considering the importance of the early diagnosis of sexually transmitted infections (STIs), the development of a sensitive and affordable method for identifying pathogens in clinical samples is needed. Highly specific and efficient primers for a multiplex polymerase chain reaction (m-PCR) system were designed in silico to detect the 16S rDNA genes of four bacteria that cause genital infections, and the PCR method was developed.

Methods

The Genosensor Probe Designer (GPD) (version 1.0a) software was initially used to design highly specific and efficient primers for in-house m-PCR. Single-locus PCR reactions were performed and standardised, and then primers for each locus in turn were added individually in subsequent amplifications until m-PCR was achieved. Amplicons of the expected size were obtained from each of the four bacterial gene fragments. Finally, the analytical specificity and limits of detection were tested.

Results

Because they did not amplify any product from non-STI tested species, the primers were specific. The detection limits for the Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum primer sets were 5.12 × 10⁵, 3.9 × 10³, 61.19 × 10⁶ and 6.37 × 10⁵ copies of a DNA template, respectively.

Conclusions

The methodology designed and standardised here could be applied satisfactorily for the simultaneous or individual detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma hominis and Ureaplasma urealyticum. This method is at least as efficient as other previously described methods; however, this method is more affordable for low-income countries.

Seroprevalence of antibodies against Pkn1, a novel potential immunogen, in Chlamydia trachomatis-infected Macaca nemestrina and human patients

Chlamydia trachomatis (CT) is an important cause of sexually transmitted genital tract infections (STIs) and trachoma. Despite major research into chlamydial pathogenesis and host immune responses, immunoprotection has been hampered by the incomplete understanding of protective immunity in the genital tract. Characterized vaccine candidates have shown variable efficacy ranging from no protection to partial protection in vivo. It is therefore a research priority to identify novel chlamydial antigens that may elicit protective immune responses against CT infection. In the present study we assessed the seroprevalence of antibodies against protein kinase1 (Pkn1), DNA ligaseA (LigA), and major outer membrane protein A (OmpA) following natural CT infection in humans and in experimentally induced CT infection in Macaca nemestrina. Antigenic stretches of Pkn1, LigA, and OmpA were identified using bioinformatic tools. Pkn1, LigA, and OmpA genes were cloned in bacterial expression vector and purified by affinity chromatography. Our results demonstrate significantly high seroprevalence of antibodies against purified Pkn1 and OmpA in sera obtained from the macaque animal model and human patients infected with CT. In contrast no significant seroreactivity was observed for LigA. The seroprevalence of antibodies against Pkn1 suggest that nonsurface chlamydial proteins could also be important for developing vaccines for C. trachomatis.

Chlamydia trachomatis infection in HIV-infected women: need for screening by a sensitive and specific test

Reproductive tract infection (RTIs)/sexually transmitted infections (STIs) are recognized as a major public health problem, particularly due to their relationship with HIV infection. Early detection and treatment of Chlamydia trachomatis infection (CTI) among HIV-infected and HIV-uninfected women may impact heterosexual HIV transmission. A total of 120 participants were enrolled: 30 HIV seropositive women with symptoms of RTIs, 30 HIV seropositive women without symptoms of RTIs, 30 HIV seronegative women with symptoms of RTIs, and 30 HIV seronegative women without symptoms of RTIs. One endocervical swab was collected from all participants and CTI was detected by real-time PCR (COBAS TaqMan CT Test, v2.0). CTI was detected in 4 (6.67%) HIV-infected women and in 1 (1.67%) HIV-uninfected woman (OR 4.214; 95% CI 0.457–38.865). Vaginal discharge was present in almost half of HIV-infected and HIV-uninfected women; lower abdominal pain was present in 11 (18.3%) of HIV-infected and in 9 (15%) of HIV-uninfected women. This study showed that CTI is more prevalent among HIV-infected females as compared to HIV-uninfected females. As the use of real-time PCR is not feasible in most hospitals, efforts should be made to develop a simple, sensitive, and specific test to identify women with CTI for prevention of sequelae and HIV transmission.

Genital Chlamydia trachomatis: an update

Chlamydia trachomatis is the most common cause of curable bacterial sexually transmitted infection (STI) worldwide. It manifests primarily as urethritis in males and endocervicitis in females. Untreated chlamydial infection in man can cause epididymitis and proctitis. Though most women with Chlamydia infection are asymptomatic or have minimal symptoms, some develop salpingitis, endometritis, pelvic inflammatory disease (PID), ectopic pregnancy and tubal factor infertility. It is associated with an increased risk for the transmission or acquisition of HIV and is also attributed to be a risk factor for the development of cervical carcinoma. Early diagnosis and treatment of infected individuals is required to prevent the spread of the disease and severe sequelae. Traditionally, tissue culture was considered the gold standard for the diagnosis. However, with the availability of newer diagnostic techniques particularly molecular methods which are not only highly sensitive and specific but are cost-effective also, the diagnosis has became fast and easy. The purpose of this review is to study the various aspects of genital C. trachomatis infection. Also the advances related to the clinical picture, various diagnostic modalities, prevention, treatment, drug resistance and control measures will be dealt with.

Proof of concept: A bioinformatic and serological screening method for identifying new peptide antigens for Chlamydia trachomatis related sequelae in women

This study aimed to identify new peptide antigens from Chlamydia (C.) trachomatis in a proof of concept approach which could be used to develop an epitope-based serological diagnostic for C. trachomatis related infertility in women. A bioinformatics analysis was conducted examining several immunodominant proteins from C. trachomatis to identify predicted immunoglobulin epitopes unique to C. trachomatis. A peptide array of these epitopes was screened against participant sera. The participants (all female) were categorized into the following cohorts based on their infection and gynecological history; acute (single treated infection with C. trachomatis), multiple (more than one C. trachomatis infection, all treated), sequelae (PID or tubal infertility with a history of C. trachomatis infection), and infertile (no history of C. trachomatis infection and no detected tubal damage). The bioinformatics strategy identified several promising epitopes. Participants who reacted positively in the peptide 11 ELISA were found to have an increased likelihood of being in the sequelae cohort compared to the infertile cohort with an odds ratio of 16.3 (95% c.i. 1.65-160), with 95% specificity and 46% sensitivity (0.19-0.74). The peptide 11 ELISA has the potential to be further developed as a screening tool for use during the early IVF work up and provides proof of concept that there may be further peptide antigens which could be identified using bioinformatics and screening approaches.

Classical and Molecular Methods for Evaluation of Chlamydia trachomatis Infection in Women with Tubal Factor Infertility

BACKGROUND

Chlamydia trachomatis is the most reported bacterial sexually transmitted disease, especially among young women worldwide. The aim of this study was comparison the prevalence of Chlamydia trachomatis infection in woman with tubal infertility by means of PCR and cell culture techniques.

METHODS

Fifty-one women with confirmed TFI were enrolled in this study in (avicenna infertility Clinic) between January 2010 and January 2011. Cervical swab and cytobrush specimens were collected from each patient by gynecologists and sent to laboratory in transport media. Detection of Chlamydia trachomatis in samples was performed using PCR and bacteria culture in MacCoy cell line. The data were analyzed by Fisher's exact test and independent t-test. Statistical significance was established at a p-value <0.05.

RESULTS

A significant relation was observed between increased the age of first intercourse and chlamydial infection. Six (11.7%) samples had positive PCR result, whereas cell culture results were positive in only 2 (3.9%) samples. A significant relation was also identified between the duration of infertility and infection (p < 0.05) by PCR versus cell culture method.

CONCLUSION

The results showed that PCR is a rapid method, compared to cell culture for detecting Chlamydial organism. It also became clear that the age at first intercourse is important to predict the likelihood of Chlamydia trachomatis.

Prevalence of cases of Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum and Chlamydia trachomatis in women with no gynecologic complaints

Purpose

To evaluate the prevalence of Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum, Chlamydia trachomatis, Trichomonas vaginalis and Neisseria gonorrhoeae in women with no gynecologic complaints screened in the Human Reproduction outpatient clinic of Faculdade de Medicina of ABC, Brazil.

Methods

A total of 106 women without gynecologic complaints and in reproductive age were evaluated. DNA was extracted from cells of the genitourinary tract with bacteria for the detection of six types of bacteria by polymerase chain reaction.

Results

We found that 11.3 % of women had infection with M. hominis and 2.83 % for C. trachomatis. The other bacteria investigated occurred in 2.83 % of women. The percentage of infections identified was 15 %.

Conclusion

The data showed a low percentage of women with genitourinary tract bacteria without symptoms. However, these infections can be sexually transmitted, and relate to infertility and other serious illnesses. The identification and treatment of infection in asymptomatic woman can avoid transmission and future genitourinary trait complications.