Chlamydial infection: an accurate model for opportunistic screening in general practice

Chlamydia-related knowledge, opinion to opportunistic testing, and practices of providers among different sexually transmitted infections related departments in hospitals in Shenzhen city, China

BACKGROUND

Chlamydia trachomatis (CT) infection could lead to seriously adverse outcomes if left untreated. This study aimed to determine CT-related knowledge, opinion to testing, and practices of providers among different sexually transmitted infections (STI) related departments in hospitals in Shenzhen city, China, and also to explore the differences in these responses.

MATERIALS AND METHODS

From 1st April 2018 to 15th April 2018, a cross-sectional study was conducted in Shenzhen and 64 of 66 hospitals agreed to participate in this study. In the hospital sites, all the providers from the department of obstetrics and gynecology, department of dermatology and venereology, department of urology, and anorectal surgical department were recruited. A structured paper-based questionnaire was used to obtain data on CT-related information.

RESULTS

A total of 355 providers from 64 hospitals participated in the current study. Compared to providers from the department of dermatology and venereology, those from the department of obstetrics and gynecology (OR = 0.31, 95% CI 0.16-0.62), department of urology (OR = 0.32, 95% CI 0.16-0.65), and anorectal surgical department (OR = 0.25, 95% CI 0.09-0.71) were less likely to identify that "Be in a long-term mutually monogamous relationship with a partner who has been tested and has negative STI test results." is an appropriate way for a sexually active person to reduce risk of getting CT. Also, those from the department of obstetrics and gynecology (OR = 0.45, 95% CI 0.23-0.87) were less likely to identify that "Use latex condoms the right way every time you have sex" is another appropriate way. A high proportion of providers agreed that all sexually active patients attending to their department should be screened regularly (77.1%), and they are willing to offer opportunistic CT screening (96.0%). Only 11.4% of respondents correctly identified that the appropriate time frame of the CT retesting is three months.

CONCLUSIONS

Providers among STI-related departments in hospitals showed a very high willingness to offer opportunistic CT screening. However, this study showed important gaps in providers' knowledge and practices in China, targeted training in CT-related knowledge and practice is urgently needed.

Enteric disease episodes and the risk of acquiring a future sexually transmitted infection: a prediction model in Montreal residents

OBJECTIVE

The sexual transmission of enteric diseases poses an important public health challenge. We aimed to build a prediction model capable of identifying individuals with a reported enteric disease who could be at risk of acquiring future sexually transmitted infections (STIs).

MATERIALS AND METHODS

Passive surveillance data on Montreal residents with at least 1 enteric disease report was used to construct the prediction model. Cases were defined as all subjects with at least 1 STI report following their initial enteric disease episode. A final logistic regression prediction model was chosen using forward stepwise selection.

RESULTS

The prediction model with the greatest validity included age, sex, residential location, number of STI episodes experienced prior to the first enteric disease episode, type of enteric disease acquired, and an interaction term between age and male sex. This model had an area under the curve of 0.77 and had acceptable calibration.

DISCUSSION

A coordinated public health response to the sexual transmission of enteric diseases requires that a distinction be made between cases of enteric diseases transmitted through sexual activity from those transmitted through contaminated food or water. A prediction model can aid public health officials in identifying individuals who may have a higher risk of sexually acquiring a reportable disease. Once identified, these individuals could receive specialized intervention to prevent future infection.

CONCLUSION

The information produced from a prediction model capable of identifying higher risk individuals can be used to guide efforts in investigating and controlling reported cases of enteric diseases and STIs.

Prevalence of chlamydia among HIV positive and HIV negative patients in the Vhembe District as detected by real time PCR from urine samples

Background

Chlamydia is a bacterial infection that has long plagued humanity as the most commonly contracted STD and is caused by Chlamydia trachomatis. With the emergence of HIV/AIDS, sexually transmitted diseases have also re-emerged as a grave public health problem, particularly in developing countries. Updated Information about the relative frequencies in developing countries is sparse. This study aims at establishing the relative occurrence of chlamydia using real time PCR technique in the Vhembe District of South Africa where reports on the prevalence of chlamydia are not available.

Methods

A total of 243 Urine samples were collected from patients attending different ARV clinics in the Vhembe District and genomic DNA was purified using blood genomic DNA kit from Sigma-Aldrich. Real-Time PCR protocol targeting the 16S rRNA gene of C. trachomatis was used to confirm the presence of chlamydia among these patients. Demographic information as well as clinical data was collected as well.

Results

Of all the participants, 70.4 % were females. The age varied from 19 to 72 years. The overall prevalence of chlamydia was 32.1 %. The prevalence was significantly higher among females (39.2 %) compared to males (15.5 %) patients (P = 0.001) and was highest among pregnant women followed by patients who had reported any allergic reaction. Among the HIV positive patients, the prevalence was higher among those who were not taking ARV (38.1 %) compared to those who were taking them (28.5 %). The age group within which the highest prevalence was found was between 26–45 years.

Conclusions

The present study shows a high prevalence of chlamydia among HIV and AIDS patients in the Vhembe District emphasizing the need to enhance STI control and particularly chlamydia among all young people. The particularly high prevalence of chlamydia among pregnant women is of great concern as this predisposes them to complications, while allergy migh predispose people to chlamydia infections. Further studies are needed in the general population both HIV positive and HIV negative persons to further determine the impact of these infections in the community.

Identification and risk assessment of Swedish youth at risk of chlamydia

AIMS

The aim of the study was to identify youth at high risk of chlamydia including variables related to sexual health and negative experiences of sexuality.

METHODS

In late 2009, a questionnaire on sexuality was answered by Swedish youth. The study sample was self-selected from different Internet communities. Data from 6544 sexually active participants, aged 15-24 years, were analyzed in a multivariable logistic regression model. Discriminative power was measured by the area under the receiver operating characteristic curve.

RESULTS

In the univariate analysis, self-reported chlamydia was associated with most risk behavior variables, experience of coerced sex, and reimbursement for sex, with slight gender variation. The factors that best predicted self-reported chlamydia among females were number of partners, age, and having been reimbursed for sex. Among males, the number of partners and alcohol consumption were the strongest predictors. Increasing number of partners up to 10 during the past 12 months was the most important predictor for both genders. A skewed distribution of chlamydia was demonstrated, in that 37.6% of cases in females and 38.6% in males were estimated to occur among a tenth of the population.

CONCLUSIONS

Testing, prevention, and care for chlamydia should be directed toward those most at risk, as they account for a large proportion of the total number of chlamydia cases. The special needs of the high-risk group need to be acknowledged and chlamydia regarded as a possible marker for risk behavior and negative sexuality experiences.

A critical appraisal of risk models for predicting sexually transmitted infections

BACKGROUND

Prediction rules have been proposed as alternatives to screening recommendations and have potential applications in sexual health decision making. To our knowledge, there has been no review undertaken providing a critical appraisal of existing prediction rules in sexual health contexts. This review aims to identify and characterize prediction rules developed and validated for sexually transmitted infection (STI) screening, describe the methodological issues essential to the suitability of derived models for clinical or public health application, and synthesize the literature on the performance of these models.

METHODS

We searched MEDLINE (2003-2012) to identify studies that reported on models predicting STIs. We explored the methodological quality of the studies based on a 16-item quality assessment checklist. We also evaluated the studies based on data extracted on model discrimination, calibration, sensitivity, and testing efficiency.

RESULTS

We identified 16 publications reporting on STI prediction rules. The most poorly addressed quality items were missing values, calibration measures, and variable definition. Overall, the performance of risk models as measured by discrimination (area under the receiver operating characteristic curve range, 0.64-0.88) and calibration was found to be generally good or satisfactory. Eight studies attained or were close to attaining the performance benchmark of testing less than 60% of the target population to achieve 90% sensitivity. The 2 risk models that were externally validated displayed adequate discrimination in new settings.

CONCLUSIONS

Although we identified several well-performing STI risk prediction rules, few have been validated. Future developments in the use of prediction rules should address their clinical consequence, comparative usefulness, external validity, and implementation impact.

Chlamydia trachomatis infection during pregnancy: knowledge, test practices, and attitudes of Dutch midwives

BACKGROUND

Chlamydia trachomatis infection in pregnancy may lead to adverse pregnancy outcomes. In the Netherlands, testing for C. trachomatis is based on risk assessment. We assessed midwives' knowledge, test practices, assessment of risk behavior, and attitudes regarding testing for C. trachomatis infection during pregnancy. We evaluated the association between midwives' characteristics and their knowledge of C. trachomatis infection in terms of symptomatology and outcomes.

METHODS

This was a cross-sectional study among primary care midwives in the Netherlands. Between September and November 2011, midwives from all Dutch primary care midwifery practices were invited to complete a questionnaire about C. trachomatis infection.

RESULTS

Of the 518 midwives invited to participate in this study, 331 (63.9%) responded. The overall median knowledge score for questions about symptomatology and outcomes was 10 out of a maximum score of 15. The median knowledge score was higher among midwives in urban areas. In total, 239 (72.2%) midwives reported testing pregnant women for C. trachomatis. The primary reason for testing was a request by the woman herself (96.2%), followed by symptoms of infection (89.1%), risk behavior (59.3%), and risk factors for infection (7.3%). Almost 25% of midwives showed positive attitudes towards universal screening for C. trachomatis.

CONCLUSIONS

Midwives were knowledgeable about symptoms of infection, but less about outcomes. Midwives test pregnant women for C. trachomatis mainly on the women's request. Otherwise, testing is based on symptoms of infection rather than on known risk factors. This may contribute to under-diagnosis and under-treatment, leading to maternal, perinatal, and neonatal morbidity.

Asking about condom use: a key to individualized care when screening for chlamydia

Chlamydia trachomatis (CT) infection has been a target for both selective and national screening programmes, and Sweden has an opportunistic approach. A national plan of action states that risk groups should be identified and offered risk reduction counselling. Patients attending a drop-in sexually transmitted infection (STI) clinic reception at the University Hospital, Umeå, Sweden, were invited to complete a questionnaire regarding sociodemographic characteristics, symptoms and sexual risk behaviour; all had a CT test taken. A total of 1305 patients were included, 58% men, mean age 27.8 years. CT prevalence was 11%; 51% of those with CT were ≥25 years old. Only 5% used a condom during the entire sexual intercourse with their last new/temporary partner. Sexually active inconsistent condom users comprised 62% of the study population and contributed to 81% of the chlamydia infections. Asking whether a condom was used could quickly triage patients into groups with a ‘higher risk’ (none or inconsistent use of condoms and at least one new/temporary partners), and ‘lower risk’ (with more consistent condom use, although not always accurate) allowing for individualized care and counselling when screening for chlamydia. Evaluating whether a condom was used throughout the sexual intercourse did not add any useful information.

Potential triggering infections of reactive arthritis

OBJECTIVES

The aim of the study was to investigate possible triggering infections causing reactive arthritis (ReA) of urogenital origin.

METHODS

One hundred and twenty ReA patients, 85 control group patients with other arthritides (61 with rheumatoid arthritis, 13 with osteoarthritis, and 11 with microcrystal arthritis), and 52 healthy persons were tested for urogenital tract inflammation and several infectious agents. Ligase chain reaction was used for detection of Chlamydia trachomatis (CT). Genital mycoplasmas Ureaplasma urealyticum (Uu) and Mycoplasma hominis (Mh) were tested using the Mycoplasma Duo Test (MDT). Only titres greater than 10(4) CCU/mL were accepted as pathogenecity threshold levels for Uu.

RESULTS

Inflammation of the urogenital tract (most frequently urethritis in men and cervicitis in women) was found in 95% of patients with acute ReA. Possible causative pathogens were identified in 58% of ReA patients. CT was found in 29%, Uu in 21%, and Mh in 8% of patients with ReA. While CT and Uu were found more often in HLA-B27-positive than in HLA-B27-negative patients, this was statistically proved only for CT. In ReA males Uu was found four times more frequently than in men with other arthritides.

CONCLUSIONS

In active ReA of urogenital origin, inflammation of the urogenital tract is found in the majority of patients. Although CT is the main microorganism associated with urethritis in men and cervicitis in women, mycoplasmas, especially Uu, may be possible aetiological factors for ReA.

Performance of a screening algorithm for chlamydial infection in 2 samples of patients in general practice

This paper evaluates the performance of an algorithm developed for opportunistic, selective screening of women for chlamydial infection in general practice in Antwerp, Belgium. Its performance was examined in 2 independent sets of patients: A) a cohort of 326 women participating in a pilot screening study, and B) a sample of 25 Chlamydia positive women, identified from the records of a laboratory of clinical microbiology. For group A, positive and negative predictive values were calculated and the accuracy of the algorithm was assessed. For group B, we examined the proportion of patients complying with the algorithm. In group A, the screening algorithm would have detected 73% of the cases in 35.6% of the population. The positive and negative predictive values were 7.7% and 98.4%, respectively. In group B, 84% of patients complied with the algorithm. The screening algorithm worked reasonably well in 2 datasets from a similar population studied 2 y later, but needs further validation.

The rate of sexually transmitted infections in ED patients with vaginal bleeding

BACKGROUND

Early diagnosis of sexually transmitted infections (STI) such as Chlamydia trachomatis (CT) and Neisseria gonorrhoea (NG) is crucial in reducing complications. Vaginal bleeding (VB) has been suggested as a possible presentation of STI.

OBJECTIVE

To identify the rate of STI in sexually active women presenting to the emergency department (ED) with VB.

METHODS

Prospective observational study of females 18-55 years-old presenting to two affiliated urban EDs with VB (convenience sample). Patients with recent STI or antibiotic use (< 3 months) were excluded. To estimate the background rate of STI, we enrolled women with no genitourinary complaints as controls. Specimens for CT and NG were obtained during speculum exam from cases and by self administered vaginal swab in controls. All specimens were analyzed by polymerase chain reaction. Continuous data was presented as mean +/- standard deviation and categorical data as percentages with 95% confidence intervals CI). Fisher's exact test was used to compare the rate of STI between the groups.

RESULTS

From 09.06 to 08.07 a total 273 subjects were enrolled (174 VB and 99 controls, mean age: 33 +/- 10). Groups were similar with regards to baseline characteristics. The majority of STI cases were due to CT: 5.8% in VB group (95% CI, 3.2%-10.4%) vs. 7.1% in controls (95% CI, 3.5%-14.0%). The STI rate was 6.3% (95% CI, 3.5%-11.1%) in VB patients and 8% (95% CI, 3.9%-15.3%) in controls.

CONCLUSIONS

Our ED patients with and without vaginal bleeding had comparable rate of STI.

Chlamydia trachomatis prevalence in Iranian women attending obstetrics and gynaecology clinics

This study was designed to estimate the prevalence of Chlamydia infection in women attending Obstetrics and Gynaecology clinics in Tehran, during May 2003 to October 2003. Women attending Obstetrics and Gynaecology clinics aged 15-42 were recruited by Sequential Random Sampling. Those who had not passed urine in the last hour were eligible. Informed consent was obtained and a questionnaire completed after being interviewed by a midwife. First void urine was collected and after DNA extraction from urine specimen, PCR tests were performed; urine DNA samples were tested by strand displacement amplification (SDA) for Chlamydia confirmation. 12.6% (133/1052) tested positive for Chlamydia by PCR. Of these PCR positive samples, 86 were available for re-testing by SDA and 67 were positive giving a correlation between the tests of 78%. This gave an overall true prevalence of 6.4% which is however, underestimated. No statistical differences were seen between patient age groups, details of personal and reproductive history and combined PCR and SDA positivity for C. trachomatis. A 12.6% prevalence of Chlamydia trachomatis was found by PCR testing which is cost effective to screen and treat. Despite limitations in re-testing PCR-positive samples by SDA, a 78% correlation between tests confirms a high prevalence of C. trachomatis. Non-invasive screening of women was therefore a success in this group of patients. As this was the first time that more sensitive molecular methods were used for detection of C. trachomatis, prevalence in such a big sample size, the results are considerable. However, we suggest further such testing.

Conversant or clueless? Chlamydia-related knowledge and practice of general practitioners in Western Australia

Background

A survey of Western Australia's general practitioners' (GPs') knowledge and practices relating to genital chlamydia infection was conducted in mid-2005, prior to a multi-media campaign which encouraged 15–24 year olds to seek chlamydia testing through their general practitioner (GP). The survey aimed to raise GPs' awareness of chlamydia in preparation for the campaign and to establish a baseline measure of their chlamydia-related knowledge and practices.

Methods

All 2038 GPs registered on the Australian Medical Publishing Company's database as practising in Western Australia were sent a survey which covered clinical features of chlamydia, investigations, treatment and public health issues; 576 (29%) responded.

Results

Most GPs were aware of chlamydia being common in the 20–24 year old age group, but less than half were aware that it is common in 15–19 year olds. GPs missed many opportunities for chlamydia testing in patients likely to be at risk of STIs, largely because they thought the patient would be embarrassed. It is of concern that public health responsibilities in relation to chlamydia, ie notification and contact tracing, were not undertaken by all GPs.

Conclusion

Australia is currently piloting chlamydia screening. For this to be successful, GPs will need to maintain current knowledge and clinical suspicion about chlamydia, and be comfortable in asking and receiving information about sexual behaviours. Only then will GPs have a significant impact on curbing Australia's ever-increasing rates of chlamydia.

The profile of emergency contraception users in a chlamydia prevalence study in primary care in Belgium

INTRODUCTION

We describe the use of emergency contraception (EC) and its association with sociodemographic, contraceptive and behavioural characteristics in a sample of family practice attendants in Belgium.

METHODS

The study was part of a large Chlamydia trachomatis (CT) prevalence study in general practice. Sexually active women under 40 who consulted their general practitioner for routine gynaecological care were enrolled in the study. Participants completed a questionnaire on sociodemographic variables, urogenital symptoms, sexual history and sexual behaviour, and delivered a sample for CT testing. Logistic regression analysis was performed to identify determinants of a history of EC use in women in this sample.

RESULTS

Of 815 questioned women, 23.5% had ever used EC. EC users were a heterogeneous group with respect to educational level, age and ethnicity. The use of emergency contraception was associated with the level of urbanisation, condom use, not having children yet, young age of first sexual intercourse, having had multiple partners in the past year, a history of unintended pregnancy, and current or previous STI.

DISCUSSION

Information on availability and correct use of EC, and on the need for additional testing for STI, are necessary to help primary care attendees to preserve their future reproductive health.

Antibiotic consumption and chlamydia prevalence in international studies

BACKGROUND

To determine whether there is an ecological association between antibiotic use and chlamydia prevalence.

METHODS

A systematic review was undertaken of international studies on chlamydia prevalence among women aged 15-25 years published between 2000 and 2005. Preference was given to studies using nucleic acid testing and representative population-based sampling methods. Data were obtained on per capita antibiotic consumption according to the defined daily dose.

RESULTS

For the 12 countries for which both antibiotic consumption and relevant prevalence data for chlamydia were available, a non-significant negative correlation was found between total antibiotic consumption per capita and chlamydia prevalence among younger women according to country (r(s) = -0.242, P = 0.449). When an outlier (from the Netherlands) was excluded, the correlation was significant (r(s) = -0.615, P = 0.044). Combined use of tetracyclines and macrolides was also associated with lower chlamydia prevalence (r(s) = -0.697, P = 0.017).

CONCLUSIONS

It is possible that antibiotics used for other reasons may have unexpectedly reduced the prevalence of chlamydia.

The clinical diagnosis of pelvic inflammatory disease--reuse of electronic medical record data from 189 patients visiting a Swedish university hospital emergency department

BACKGROUND

The pelvic inflammatory disease (PID) diagnosis is mostly based on clinical findings. However, few studies have examined the clinical basis for the diagnostics of PID, which was the aim of this study.

METHODS

A retrospective study was performed of 189 out-patients diagnosed as having PID at the obstetric and gynecological emergency department of a Swedish university hospital. Data on symptoms, signs, pelvic examination and laboratory tests were extracted from the electronic medical records in comparison with the diagnostic criteria of the PID Guideline of the US Center of Disease Control from 2002 (CDC 2002 Guidelines).

RESULTS

Eight symptoms in varying combinations were associated with the PID diagnosis. Most of them are mentioned in the CDC 2002 Guidelines. Detected rates of C. Trachomatis (CT) and N. Gonorrhoeae (NG) were 5% and 0%, respectively, among the tested patients (CT = 52% and NG = 12%). The C-reactive protein was normal in the majority of tested patients.

CONCLUSION

The clinical basis for the diagnostics of PID was largely in accordance with the criteria in the CDC 2002 Guidelines. The limited number of CT tests performed is somewhat disappointing, considering the fact that effective disease prevention includes widespread CT screening. Further studies in different settings are needed in order to analyze how the testing rate for CT can be improved in clinical praxis.

Willingness to offer chlamydia testing in general practice in New South Wales

OBJECTIVES

To assess willingness of general practitioners (GPs) to offer chlamydia testing to patients, and to identify demographic and practice correlates associated with willingness to offer chlamydia testing.

METHODS

A postal survey of practising GPs in New South Wales was undertaken in 2002 to assess management of STIs in general practice. A 15% (n = 1,020) stratified random sample, based on sex and area of practice, was selected. The overall response rate was 45.4% (n = 409).

RESULTS

More than four out of five study participants reported that chlamydia testing should usually be offered to patients who had recently changed sexual partners or inconsistently used barrier methods such as condoms. While 76% of GPs would like to offer testing to young women, 65% were in favour of testing young men. Just over half (56%) felt that chlamydia testing should usually be offered to patients at the time of a Pap smear. Multivariate analyses revealed that female GPs were more likely to offer testing to young patients and to female patients at the time of a Pap smear. GPs who had postgraduate training in STls had double the odds of offering testing to young men and to female patients at the time of a Pap smear.

CONCLUSIONS AND IMPLICATIONS

This paper reveals variations in GPs' willingness to offer chlamydia testing to patients. Special education programs highlighting the adverse health effects of chlamydial infection have the potential to improve GP involvement in chlamydia screening.

Prediction of Chlamydia trachomatis Infection: Application of a Scoring Rule to Other Populations

BACKGROUND

Active case finding is crucial to reduce transmission and consequences of Chlamydia trachomatis (CT) infections. We previously proposed the use of a prediction rule for CT infection for selective screening of high-risk individuals in a population. To support such an application, the prediction rule needs to be validated in other populations.

METHODS

We studied participants aged 15 to 29 years in a population-based study in Amsterdam (n = 1,788) and an outreach screening project among high-risk youth in Rotterdam (n = 172). Validity was indicated by discriminative ability (area under the receiver operating characteristic curve [AUC]) and by calibration, which was visualized in plots and tested with the Hosmer-Lemeshow (H-L) goodness-of-fit test. Cutoffs of predicted risk were examined for their effect on sensitivity and the fraction of participants that would need to be screened.

RESULTS

Discriminative ability was reasonable both for the Amsterdam study (AUC 0.66; 95% confidence interval [CI], 0.58-0.74) and for the Rotterdam study (AUC 0.68; 95% CI, 0.58-0.79). The observed CT prevalence was lower than predicted in Amsterdam (H-L P = 0.02) and nonsignificantly higher in Rotterdam (H-L P = 0.20). By screening 77% of the Amsterdam population, 93% of the cases would have been detected, whereas in the Rotterdam study, no cases would be missed by screening 75%.

CONCLUSION

The chlamydia prediction rule showed a reasonable external validity in two studies. These findings support the use of the rule as a tool for selective chlamydia screening, although only a limited fraction of participants can be excluded when a high sensitivity is required.

A systematic review of postcoital bleeding and risk of cervical cancer

BACKGROUND

Postcoital bleeding may be a symptom of cervical cancer. Guidance to aid a GP in determining whom to investigate or refer exists but recommendations vary. Women need to be involved in decisions about their care and this involves communicating risk and an exploration of the implications of the risk. Risk estimates of postcoital bleeding for cervical cancer are not available.

AIM

To provide an estimate of the positive predictive values of postcoital bleeding for cervical cancer to aid decision making in primary care about whom to investigate for cervical cancer.

DESIGN OF STUDY

A systematic review.

SETTING

Community, primary and secondary care.

METHOD

Six electronic databases were searched from the beginning of each of their time frames. Inclusion criteria were that the study was published in English and reported or contained enough data to calculate the prevalence or incidence of postcoital bleeding within the study population. No studies were excluded on issues of methodological quality.

RESULTS

The search strategy identified 910 unique articles. The point prevalence of postcoital bleeding in the community ranged from 0.7 to 9% among women. One study reported an annual cumulative incidence of 6% of menstruating women. The prevalence of postcoital bleeding in women with cervical cancer ranged from 0.7 to 39%. Calculation of risk that a woman in the community developing postcoital bleeding has cervical cancer ranges from 1 in 44,000 at age 20-24 years to 1 in 2 400 aged 45-54 years. There was no information allowing the direct calculation of risk in women presenting to primary care.

CONCLUSION

The evidence base for management strategies of postcoital bleeding and calculations of risk for cervical cancer in women with postcoital bleeding are poor. Recommendations for clinical practice are made on the current evidence.

Implementation of a pilot programme for screening for chlamydial infection in general practice

OBJECTIVES

To determine whether opportunistic screening for Chlamydia trachomatis, based on a selective screening, algorithm, is possible in general practice in Belgium; to assess feasibility of the screening strategy with respect to workload, acceptability, and organisational aspects.

METHODS

Implementation of a pilot screening programme by 37 GPs for a period of 15 weeks. GPs' screening practices were registered and compared with the guidelines they had received. Outcome measures were: the number of patients included in the risk assessment, uptake of screening by eligible patients, prevalence of previously unidentified infection, and uptake of treatment. After the study period GPs evaluated a number of feasibility issues on a scoring form.

RESULTS

326 women underwent the risk assessment and 214 were tested by an amplification assay on a urine sample. Prevalence in woman at risk was 6.4%. Overall effective screening rate was 77.6%; 9 of 11 positives took up treatment. Participating GPs found the strategy feasible and perceived that it was well accepted by their patients.

DISCUSSION

The screening strategy was easily implemented by most GPs but some of them dropped out. The guidelines were followed relatively well and there were no major logistic problems. The uptake of treatment wat suboptimal. Efforts must be made to stimulate and educate more GPs to perform screening; laboratory and storage conditions should be optimised; refunding criteria should be revised; and overscreening must be avoided.

A short educational intervention on communication skills improves the quality of screening for Chlamydia in GPs in Belgium: a cluster randomised controlled trial

An accurate algorithm for screening for chlamydial infections is available in general practice, but GPs experience numerous barriers to sexually transmitted infections (STI) counselling. In this study we assessed if a short educational package, under the form of a commented video footage on communication skills, was helpful in implementing the screening strategy. A cluster randomised controlled trial was carried out in 36 general practitioners in Antwerp, Belgium. Main outcome measures were: number of patients included in the risk assessment, number of patients tested, and proportion of appropriately tested patients. The results show that GPs in the intervention group did not include more patients overall, but that the quality of the screening process was significantly better (81.6% versus 56.2% appropriate tests, P = 0.02). Conclusively, GPs who participated in a short educational package on communication skills, selected eligible candidates for screening more accurately and decreased the risk of overscreening.

A prediction rule for selective screening of Chlamydia trachomatis infection

BACKGROUND

Screening for Chlamydia trachomatis infections is aimed at the reduction of these infections and subsequent complications. Selective screening may increase the cost effectiveness of a screening programme. Few population based systematic screening programmes have been carried out and attempts to validate selective screening criteria have shown poor performance. This study describes the development of a prediction rule for estimating the risk of chlamydial infection as a basis for selective screening.

METHODS

A population based chlamydia screening study was performed in the Netherlands by inviting 21,000 15-29 year old women and men in urban and rural areas for home based urine testing. Multivariable logistic regression was used to identify risk factors for chlamydial infection among 6303 sexually active participants, and the discriminative ability was measured by the area under the receiver operating characteristic curve (AUC). Internal validity was assessed with bootstrap resampling techniques.

RESULTS

The prevalence of C trachomatis (CT) infection was 2.6% (95% CI 2.2 to 3.2) in women and 2.0% (95% CI 1.4 to 2.7) in men. Chlamydial infection was associated with high level of urbanisation, young age, Surinam/Antillian ethnicity, low/intermediate education, multiple lifetime partners, a new contact in the previous two months, no condom use at last sexual contact, and complaints of (post)coital bleeding in women and frequent urination in men. A prediction model with these risk factors showed adequate discriminative ability at internal validation (AUC 0.78).

CONCLUSION

The prediction rule has the potential to guide individuals in their choice of participation when offered chlamydia screening and is a promising tool for selective CT screening at population level.

Chlamydia trachomatis in female sex workers in Belgium: 1998-2003

OBJECTIVE

We analysed the results of a 6 year screening period for Chlamydia trachomatis in a group of female sex workers (FSW) of all ages in Ghent, Belgium.

METHODS

They were tested in the context of an outreach health programme for sex workers. C trachomatis was tested by Cobas Amplicor CT/NG PCR.

RESULTS

In the 6 year period, 1643 tests were performed on 950 different sex workers (nationality: Belgian 60.3%, other western European (mostly French) 21.0%, African 12.4%, eastern European 3.0%, other 3.3%; workplace: bar/sauna 49.0%, private homes 31.8%, windows 18.2%, and escorts 1.0%). Baseline prevalence (only considering results of first test) was 70/950 or 7.4% (95% CI 5.7 to 9.0). The incidence rate was 98 episodes in 1347 person years or 7.3/100 person years (95% CI 5.9 to 8.7). There was a strong age effect. There was no clear relation with nationality or the workplace.

CONCLUSIONS

The prevalence was higher than in general populations selected in Belgium, Britain, and the Netherlands. Since younger age is a risk factor for C trachomatis, it is very important to contact these women as soon as possible when they enter the trade. General screening for C trachomatis in young women is not common practice in Belgium. Sex workers often do not tell doctors about their work and will therefore not be screened unless in the context of specific outreach projects.

Prevalence of urogenital Chlamydia trachomatis increases significantly with level of urbanisation and suggests targeted screening approaches: results from the first national population based study in the Netherlands

OBJECTIVES

Chlamydia trachomatis (Chlamydia) is the most prevalent sexually transmitted bacterial infection and can cause considerable reproductive morbidity in women. Chlamydia screening programmes have been considered but policy recommendations are hampered by the lack of population based data. This paper describes the prevalence of Chlamydia in 15-29 year old women and men in rural and urban areas, as determined through systematic population based screening organised by the Municipal Public Health Services (MHS), and discusses the implications of this screening strategy for routine implementation.

METHODS

Stratified national probability survey according to "area address density" (AAD). 21 000 randomly selected women and men in four regions, aged 15-29 years received a home sampling kit. Urine samples were returned by mail and tested by polymerase chain reaction (PCR). Treatment was via the general practitioner, STI clinic, or MHS clinic.

RESULTS

41% (8383) responded by sending in urine and questionnaire. 11% (2227) returned a refusal card. Non-responders included both higher and lower risk categories. Chlamydia prevalence was significantly lower in rural areas (0.6%, 95% CI 0.1 to 1.1) compared with very highly urbanised areas (3.2%, 95% CI 2.4 to 4.0). Overall prevalence was 2.0% (95% CI 1.7 to 2.3): 2.5% (95% CI 2.0 to 3.0%) in women and 1.5% (95% CI 1.1 to 1.8) in men. Of all cases 91% were treated. Infection was associated with degree of urbanisation, ethnicity, number of sex partners, and symptoms.

CONCLUSION

This large, population based study found very low prevalence in rural populations, suggesting that nationwide systematic screening is not indicated in the Netherlands and that targeted approaches are a better option. Further analysis of risk profiles will contribute to determine how selective screening can be done.

Do the characteristics of sexual health centre clients predict chlamydia infection sufficiently strongly to allow selective screening?

Objectives: This study aimed to estimate chlamydia prevalence and risk factors for infection and to assess the performance of chlamydia-selective screening criteria among clients attending a large sexually transmitted infection (STI) clinic. Methods: Computerised records for all attendances between 1 July 2002 and 30 June 2003 were analysed. Chlamydia prevalence and risk factors for infection were determined for all new clients. The sensitivity and specificity of risk factors for chlamydia were assessed. Results: 2642 male and 2084 female new clients were tested for chlamydia with a prevalence of 7.3% (95% CI: 6.3%, 8.4%) among men and 3.9% (95% CI: 3.1%, 4.9%) among women. Screening heterosexual men based on a positive contact or symptoms of non-specific urethritis or any two of age < 25 years, 4+ partners last 12 months, inconsistent condom use or not presenting for an asymptomatic screen detected 88% of infections by screening 62%. Screening women based on a positive contact or injecting drug use or any two of age < 25 years, 2+ partners last 12 months or inconsistent condom use would detect 86% of infections by screening 57%. Conclusions: Selective screening could be used to more efficiently identify heterosexual men and women at risk of chlamydia.