What is the cost of pelvic inflammatory disease and how much could be prevented by screening for Chlamydia trachomatis? Cost analysis of the Prevention Of Pelvic Infection (POPI) trial

Behavioural intervention to reduce sexually transmitted infections in people aged 16–24 years in the UK: the safetxt RCT

Background

The prevalence of genital chlamydia and gonorrhoea is higher in the 16–24 years age group than those in other age group. With users, we developed the theory-based safetxt intervention to reduce sexually transmitted infections.

Objectives

To establish the effect of the safetxt intervention on the incidence of chlamydia/gonorrhoea infection at 1  year.

Design

A parallel-group, individual-level, randomised superiority trial in which care providers and outcome assessors were blinded to allocation.

Setting

Recruitment was from 92 UK sexual health clinics.

Participants

Inclusion criteria were a positive chlamydia or gonorrhoea test result, diagnosis of non-specific urethritis or treatment started for chlamydia/gonorrhoea/non-specific urethritis in the last 2 weeks; owning a personal mobile phone; and being aged 16–24 years.

Allocation

Remote computer-based randomisation with an automated link to the messaging system delivering intervention or control group messages.

Intervention

The safetxt intervention was designed to reduce sexually transmitted infection by increasing partner notification, condom use and sexually transmitted infection testing before sex with new partners. It employed educational, enabling and incentivising content delivered by 42–79 text messages over 1 year, tailored according to type of infection, gender and sexuality.

Comparator

A monthly message regarding trial participation.

Main outcomes

The primary outcome was the incidence of chlamydia and gonorrhoea infection at 12 months, assessed using nucleic acid amplification tests. Secondary outcomes at 1 and 12 months included self-reported partner notification, condom use and sexually transmitted infection testing prior to sex with new partner(s).

Results

Between 1 April 2016 and 23 November 2018, we assessed 20,476 people for eligibility and consented and randomised 6248 participants, allocating 3123 to the safetxt intervention and 3125 to the control. Primary outcome data were available for 4675 (74.8%) participants. The incidence of chlamydia/gonorrhoea infection was 22.2% (693/3123) in the intervention group and 20.3% (633/3125) in the control group (odds ratio 1.13, 95% confidence interval 0.98 to 1.31). There was no evidence of heterogeneity in any of the prespecified subgroups. Partner notification was 85.6% in the intervention group and 84.0% in the control group (odds ratio 1.14, 95% confidence interval 0.99 to 1.33). At 12 months, condom use at last sex was 33.8% in the intervention group and 31.2% in the control group (odds ratio 1.14, 95% confidence interval 1.01 to 1.28) and condom use at first sex with most recent new partner was 54.4% in the intervention group and 48.7% in the control group (odds ratio 1.27, 95% confidence interval 1.11 to 1.45). Testing before sex with a new partner was 39.5% in the intervention group and 40.9% in the control group (odds ratio 0.95, 95% confidence interval 0.82 to 1.10). Having two or more partners since joining the trial was 56.9% in the intervention group and 54.8% in the control group (odds ratio 1.11, 95% confidence interval 1.00 to 1.24) and having sex with someone new since joining the trial was 69.7% in the intervention group and 67.4% in the control group (odds ratio 1.13, 95% confidence interval 1.00 to 1.28). There were no differences in safety outcomes. Additional sensitivity and per-protocol analyses showed similar results.

Limitations

Our understanding of the mechanism of action for the unanticipated effects is limited.

Conclusions

The safetxt intervention did not reduce chlamydia and gonorrhoea infections, with slightly more infections in the intervention group. The intervention increased condom use but also increased the number of partners and new partners. Randomised controlled trials are essential for evaluating health communication interventions, which can have unanticipated effects.

Future work

Randomised controlled trials evaluating novel interventions in this complex area are needed.

Trial registration

This trial is registered as ISRCTN64390461.

Funding

This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 11, No. 1. See the NIHR Journals Library website for further project information.

Testing for Mycoplasma genitalium in pelvic inflammatory disease: A clinical audit

The records of women attending Gold Coast health hospital sites were retrospectively analysed to determine if women diagnosed with pelvic inflammatory disease (PID) were being tested for Mycoplasma genitalium (MG). Only 11.4% of 299 women were tested for MG despite 74.2% being tested for Chlamydia trichomonas (CT) and Neisseria gonorrhoeae (NG). Only 9% of the women were treated with antibiotics which would treat macrolide-sensitive MG infection. Increasing education and awareness of MG and utilising reflex macrolide testing for MG will help direct effective antibiotic therapy and prevent the long-term sequalae of PID.

Pelvic inflammatory disease in the adolescent and young adult: An update

Pelvic inflammatory disease (PID) is an infection of the female upper genital tract that is typically polymicrobial with classic core involvement of Neisseria gonorrhoeae and/or Chlamydia trachomatis, though other endogenous flora from the vagino-cervical areas can be involved as well. It is often a sexually transmitted disease but other etiologic routes are also noted. A variety of risk factors have been identified including adolescence, young adulthood, adolescent cervical ectropion, multiple sexual partners, immature immune system, history of previous PID, risky contraceptive practices and others. An early diagnosis and prompt treatment are necessary to reduce risks of PID complications such as chronic pelvic pain, ectopic pregnancy and infertility. Current management principles of PID are also reviewed. It is important for clinicians to screen sexually active females for common sexually transmitted infections such as Chlamydia trachomatis and provide safer sex education to their adolescent and young adult patients. Clinicians should provide comprehensive management to persons with PID and utilize established guidelines such as those from the US Centers for Disease Control and Prevention (CDC).

[Update of Chlamydia trachomatis infection]

Chlamydia trachomatis (CT) is the most common sexually transmitted bacterial infection worldwide. It is asymptomatic in most cases and mainly affects young women, with potential long term sequelae (pelvic inflammatory disease, tubal infertility, obstetric complications). The impact on male fertility is controversial. Screening methods as well as antibiotics use have recently been reassessed due to resistance phenomena and the negative effect on the urogenital microbiota. Positive CT serology may be indicative of tuboperitoneal pathology, which may not be noticed on hysterosalpingography. New research on single-nucleotide polymorphisms (SNPs) aims to establish a patient profile at higher risk of infectious tubal damage due to CT. CT seropositivity is also associated with decreased spontaneous pregnancy rates and is a predictive factor for obstetrical complications.

Recent progress and challenges on the bioassay of pathogenic bacteria

The present review (containing 242 references) illustrates the importance and application of optical and electrochemical methods as well as their performance improvement using various methods for the detection of pathogenic bacteria. The application of advanced nanomaterials including hyper branched nanopolymers, carbon-based materials and silver, gold and so on. nanoparticles for biosensing of pathogenic bacteria was also investigated. In addition, a summary of the applications of nanoparticle-based electrochemical biosensors for the identification of pathogenic bacteria has been provided and their advantages, detriments and future development capabilities was argued. Therefore, the main focus in the present review is to investigate the role of nanomaterials in the development of biosensors for the detection of pathogenic bacteria. In addition, type of nanoparticles, analytes, methods of detection and injection, sensitivity, matrix and method of tagging are also argued in detail. As a result, we have collected electrochemical and optical biosensors designed to detect pathogenic bacteria, and argued outstanding features, research opportunities, potential and prospects for their development, according to recently published research articles.

Moxibustion for treating chronic pelvic inflammatory disease: A protocol for systematic review and meta-analysis

BACKGROUND

Chronic pelvic inflammatory disease (CPID) is a difficult-to-treat gynaecological disorder, which has complex etiologies, among married women. In recent years, moxibustion has gradually shown its clinical advantages and been more and more widely used In China. The protocol is try to synthesize and assess the effectiveness and safety of moxibustion for patients with CPID.

METHODS

Seven databases as following: PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, WangFang Database, Chinese Scientific Journal Database, Chinese Biomedical Literatures Database will be searched from their inception to May 2020. No restrictions about language and status. Study selection, data collection, and quality assessment will be respectively conducted by 2 researchers. Based on the heterogeneity test results, the fixed-effects or random-effects model will be selected to synthesize data. The effective rate, Pelvic inflammatory mass diameter and Pelvic fluid depth will be the primary outcomes. Patient reported outcome scale, visual analog scale, C-reactive protein, transforming growth factor β1 =  transforming growth factor β, incidence of any adverse events will be the secondary outcomes. Revman 5.4 software will be implemented for data synthesis. Dichotomous data will be represented by risk ratio for efficacy and safety of CPID treated with moxibustion, while continuous data will be represented by mean difference with a 95% confidence interval.

RESULTS

The results of this study will be published in a peer-reviewed journal. This study will provide a comprehensive review of the available evidence for the treatment of moxibustion with CPID.

CONCLUSIONS

This study expects to provide high-quality, evidence-based recommendations on further treatment for clinical guidance of CPID.

TRIAL REGISTRATION NUMBER

CRD42020158744 in PROSPERO 2020.

Antibiotic therapy for pelvic inflammatory disease

BACKGROUND

Pelvic inflammatory disease (PID) affects 4% to 12% of women of reproductive age. The main intervention for acute PID is broad-spectrum antibiotics administered intravenously, intramuscularly or orally. We assessed the optimal treatment regimen for PID.  OBJECTIVES: To assess the effectiveness and safety of antibiotic regimens to treat PID.

SEARCH METHODS

In January 2020, we searched the Cochrane Sexually Transmitted Infections Review Group's Specialized Register, which included randomized controlled trials (RCTs) from 1944 to 2020, located through hand and electronic searching; CENTRAL; MEDLINE; Embase; four other databases; and abstracts in selected publications.

SELECTION CRITERIA

We included RCTs comparing antibiotics with placebo or other antibiotics for the treatment of PID in women of reproductive age, either as inpatient or outpatient treatment. We limited our review to a comparison of drugs in current use that are recommended by the 2015 US Centers for Disease Control and Prevention guidelines for treatment of PID.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Two authors independently extracted data, assessed risk of bias and conducted GRADE assessments of the quality of evidence.

MAIN RESULTS

We included 39 RCTs (6894 women) in this review, adding two new RCTs at this update. The quality of the evidence ranged from very low to high, the main limitations being serious risk of bias (due to poor reporting of study methods and lack of blinding), serious inconsistency, and serious imprecision. None of the studies reported quinolones and cephalosporins, or the outcomes laparoscopic evidence of resolution of PID based on physician opinion or fertility outcomes. Length of stay results were insufficiently reported for analysis. Regimens containing azithromycin versus regimens containing doxycycline We are uncertain whether there was a clinically relevant difference between azithromycin and doxycycline in rates of cure for mild-moderate PID (RR 1.18, 95% CI 0.89 to 1.55; 2 RCTs, 243 women; I² = 72%; very low-quality evidence). The analyses may result in little or no difference between azithromycin and doxycycline in rates of severe PID (RR 1.00, 95% CI 0.96 to 1.05; 1 RCT, 309 women; low-quality evidence), or adverse effects leading to discontinuation of treatment (RR 0.71, 95% CI 0.38 to 1.34; 3 RCTs, 552 women; I² = 0%; low-quality evidence). In a sensitivity analysis limited to a single study at low risk of bias, azithromycin probably improves the rates of cure in mild-moderate PID (RR 1.35, 95% CI 1.10 to 1.67; 133 women; moderate-quality evidence), compared to doxycycline.  Regimens containing quinolone versus regimens containing cephalosporin The analysis shows there may be little or no clinically relevant difference between quinolones and cephalosporins in rates of cure for mild-moderate PID (RR 1.05, 95% CI 0.98 to 1.14; 4 RCTs, 772 women; I² = 15%; low-quality evidence), or severe PID (RR 1.06, 95% CI 0.91 to 1.23; 2 RCTs, 313 women; I² = 7%; low-quality evidence). We are uncertain whether there was a difference between quinolones and cephalosporins in adverse effects leading to discontinuation of treatment (RR 2.24, 95% CI 0.52 to 9.72; 6 RCTs, 1085 women; I² =  0%; very low-quality evidence). Regimens with nitroimidazole versus regimens without nitroimidazole There was probably little or no difference between regimens with or without nitroimidazoles (metronidazole) in rates of cure for mild-moderate PID (RR 1.02, 95% CI 0.95 to 1.09; 6 RCTs, 2660 women; I² = 50%; moderate-quality evidence), or severe PID (RR 0.96, 95% CI 0.92 to 1.01; 11 RCTs, 1383 women; I² = 0%; moderate-quality evidence). The evidence suggests that there was little to no difference in in adverse effects leading to discontinuation of treatment (RR 1.05, 95% CI 0.69 to 1.61; 17 studies, 4021 women; I² = 0%; low-quality evidence). . In a sensitivity analysis limited to studies at low risk of bias, there was little or no difference for rates of cure in mild-moderate PID (RR 1.05, 95% CI 1.00 to 1.12; 3 RCTs, 1434 women; I² = 0%; high-quality evidence). Regimens containing clindamycin plus aminoglycoside versus quinolone We are uncertain whether quinolone have little to no effect in  rates of cure for mild-moderate PID compared to clindamycin plus aminoglycoside (RR 0.88, 95% CI 0.69 to 1.13; 1 RCT, 25 women; very low-quality evidence). The analysis may result in little or no difference between quinolone vs. clindamycin plus aminoglycoside in severe PID (RR 1.02, 95% CI 0.87 to 1.19; 2 studies, 151 women; I² =  0%; low-quality evidence). We are uncertain whether quinolone reduces adverse effects leading to discontinuation of treatment (RR 0.21, 95% CI 0.02 to 1.72; 3 RCTs, 163 women; I² =  0%; very low-quality evidence). Regimens containing clindamycin plus aminoglycoside versus regimens containing cephalosporin We are uncertain whether clindamycin plus aminoglycoside improves the rates of cure for mild-moderate PID compared to cephalosporin (RR 1.02, 95% CI 0.95 to 1.09; 2 RCTs, 150 women; I² =  0%; low-quality evidence). There was probably little or no difference in rates of cure in severe PID with clindamycin plus aminoglycoside compared to cephalosporin (RR 1.00, 95% CI 0.95 to 1.06; 10 RCTs, 959 women; I²= 21%; moderate-quality evidence). We are uncertain whether clindamycin plus aminoglycoside reduces adverse effects leading to discontinuation of treatment compared to cephalosporin (RR 0.78, 95% CI 0.18 to 3.42; 10 RCTs, 1172 women; I² =  0%; very low-quality evidence).

AUTHORS' CONCLUSIONS

We are uncertain whether one treatment was safer or more effective than any other for the cure of mild-moderate or severe PID Based on a single study at a low risk of bias, a macrolide (azithromycin) probably improves the rates of cure of mild-moderate PID, compared to tetracycline (doxycycline).

Antibiotic therapy for pelvic inflammatory disease: an abridged version of a Cochrane systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To assess the effectiveness and safety of antibiotic regimens used to treat pelvic inflammatory disease (PID).

DESIGN

This is a systematic review and meta-analysis of randomised controlled trials (RCTs). Risk of bias was assessed using the criteria outlined in the Cochrane guidelines. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation.

DATA SOURCES

Eight electronic databases were searched from date of inception up to July 2016. Database searches were complemented by screening of reference lists of relevant studies, trial registers, conference proceeding abstracts and grey literature.

ELIGIBILITY CRITERIA

RCTs comparing the use of antibiotics with placebo or other antibiotics for the treatment of PID in women of reproductive age, either as inpatient or outpatient treatment.

RESULTS

We included 37 RCTs (6348 women). The quality of evidence ranged from very low to high, the main limitations being serious risk of bias (due to poor reporting of study methods and lack of blinding), serious inconsistency and serious imprecision. There was no clear evidence of a difference in the rates of cure for mild-moderate or for severe PID for the comparisons of azithromycin versus doxycycline, quinolone versus cephalosporin, nitroimidazole versus no use of nitroimidazole, clindamycin plus aminoglycoside versus quinolone, or clindamycin plus aminoglycoside versus cephalosporin. No clear evidence of a difference between regimens in antibiotic-related adverse events leading to discontinuation of therapy was observed.

CONCLUSIONS

We found no conclusive evidence that one regimen of antibiotics was safer or more effective than any other for the treatment of PID, and there was no clear evidence for the use of nitroimidazoles (metronidazole) compared with the use of other drugs with activity against anaerobes. More evidence is needed to assess treatments for women with PID, particularly comparing regimens with or without the addition of nitroimidazoles and the efficacy of azithromycin compared with doxycycline.

Modelling-based evaluation of the costs, benefits and cost-effectiveness of multipathogen point-of-care tests for sexually transmitted infections in symptomatic genitourinary medicine clinic attendees

OBJECTIVES

To quantify the costs, benefits and cost-effectiveness of three multipathogen point-of-care (POC) testing strategies for detecting common sexually transmitted infections (STIs) compared with standard laboratory testing.

DESIGN

Modelling study.

SETTING

Genitourinary medicine (GUM) services in England.

POPULATION

A hypothetical cohort of 965 988 people, representing the annual number attending GUM services symptomatic of lower genitourinary tract infection.

INTERVENTIONS

The decision tree model considered costs and reimbursement to GUM services associated with diagnosing and managing STIs. Three strategies using hypothetical point-of-care tests (POCTs) were compared with standard care (SC) using laboratory-based testing. The strategies were: A) dual POCT for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG); B) triplex POCT for CT-NG and Mycoplasma genitalium (MG); C) quadruplex POCT for CT-NG-MG and Trichomonas vaginalis (TV). Data came from published literature and unpublished estimates.

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcomes were total costs and benefits (quality-adjusted life years (QALYs)) for each strategy (2016 GB, £) and associated incremental cost-effectiveness ratios (ICERs) between each of the POC strategies and SC. Secondary outcomes were inappropriate treatment of STIs, onward STI transmission, pelvic inflammatory disease in women, time to cure and total attendances.

RESULTS

In the base-case analysis, POC strategy C, a quadruplex POCT, was the most cost-effective relative to the other strategies, with an ICER of £36 585 per QALY gained compared with SC when using microcosting, and cost-savings of £26 451 382 when using tariff costing. POC strategy C also generated the most benefits, with 240 467 fewer clinic attendances, 808 fewer onward STI transmissions and 235 135 averted inappropriate treatments compared with SC.

CONCLUSIONS

Many benefits can be achieved by using multipathogen POCTs to improve STI diagnosis and management. Further evidence is needed on the underlying prevalence of STIs and SC delivery in the UK to reduce uncertainty in economic analyses.

'Test n Treat (TnT)'- Rapid testing and same-day, on-site treatment to reduce rates of chlamydia in sexually active further education college students: study protocol for a cluster randomised feasibility trial

BACKGROUND

Sexually active young people attending London further education (FE) colleges have high rates of chlamydia, but screening rates are low. We will conduct a cluster randomised feasibility trial of frequent, rapid, on-site chlamydia testing and same-day treatment (Test and Treat (TnT)) in six FE colleges (with parallel qualitative and economic assessments) to assess the feasibility of conducting a future trial to investigate if TnT reduces chlamydia rates.

METHODS

We will recruit 80 sexually active students aged 16-24 years from public areas at each of six colleges. All participants (total n = 480) will be asked to provide samples (urine for males, self-taken vaginal swabs for females) and complete questionnaires on sexual lifestyle and healthcare use at baseline and after 7 months. Participants will be informed that baseline samples will not be tested for 7 months and be advised to get screened separately. Colleges will be randomly allocated to the intervention (TnT) or the control group (no TnT). One and 4 months after recruitment, participants at each intervention college (n = 3) will be texted and invited for on-site chlamydia tests using the 90-min Cepheid GeneXpert system. Students with positive results will be asked to see a visiting nurse health adviser for same-day treatment and partner notification, (backed by genitourinary medicine follow-up). Participants in control colleges (n = 3) will receive 'thank you' texts 1 and 4 months after recruitment. Seven months after recruitment, participants from both groups will be invited to complete questionnaires and provide samples for TnT. All samples will be tested, and same-day treatment offered to students with positive results. Acceptability of TnT will be assessed by qualitative interviews of purposively sampled students (n = 30) and college staff (n = 12). We will collect data on costs of TnT and usual healthcare.

DISCUSSION

Findings will provide key values to inform feasibility, sample size and timescales of a future definitive trial of TnT in FE colleges, including: Recruitment rates TnT uptake rates Follow-up rates Prevalence of chlamydia in participants at baseline and 7 months Acceptability of TnT to students and college staff Estimate of the cost per person screened/treated in TnT versus usual care TRIAL REGISTRATION: International Standard Randomised Controlled Trials Registry, ID: ISRCTN58038795 , Registered on 31 August 2016.

Antibiotic therapy for pelvic inflammatory disease

BACKGROUND

Pelvic inflammatory disease (PID) is an infection that affects 4% to 12% of young women, and is one of the most common causes of morbidity in this age group. The main intervention for acute PID is the use of broad-spectrum antibiotics which cover Chlamydia trachomatis, Neisseria gonorrhoeae, and anaerobic bacteria, administered intravenously, intramuscularly, or orally. In this review, we assessed the optimal treatment regimen for PID.

OBJECTIVES

To assess the effectiveness and safety of antibiotic regimens used to treat pelvic inflammatory disease.

SEARCH METHODS

We searched the Cochrane Sexually Transmitted Infections Review Group's Specialized Register, which included randomized controlled trials (RCTs) from 1944 to 2016, located through electronic searching and handsearching; the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid platform (1991 to July 2016); MEDLINE (1946 to July 2016); Embase (1947 to July 2016); LILACS, iAHx interface (1982 to July 2016); World Health Organization International Clinical Trials Registry Platform (July 2016); Web of Science (2001 to July 2016); OpenGrey (1990, 1992, 1995, 1996, and 1997); and abstracts in selected publications.

SELECTION CRITERIA

We included RCTs comparing the use of antibiotics with placebo or other antibiotics for the treatment of PID in women of reproductive age, either as inpatient or outpatient treatment. We limited our review to comparison of drugs in current use that are recommended for consideration by the 2015 US Centers for Disease Control and Prevention (CDC) guidelines for treatment of PID.

DATA COLLECTION AND ANALYSIS

At least two review authors independently selected trials for inclusion, extracted data, and assessed risk of bias. We contacted investigators to obtain missing information. We resolved disagreements by consensus or by consulting a fourth review author if necessary. We assessed the quality of the evidence using GRADE criteria, classifying it as high, moderate, low, or very low. We calculated Mantel-Haenszel risk ratios (RR), using either random-effects or fixed-effect models and number needed to treat for an additional beneficial outcome or for an additional harmful outcome, with their 95% confidence interval (CI), to measure the effect of the treatments. We conducted sensitivity analyses limited to studies at low risk of bias, for comparisons where such studies were available.

MAIN RESULTS

We included 37 RCTs (6348 women). The quality of the evidence ranged from very low to high, the main limitations being serious risk of bias (due to poor reporting of study methods and lack of blinding), serious inconsistency, and serious imprecision. Azithromycin versus doxycyclineThere was no clear evidence of a difference between the two drugs in rates of cure for mild-moderate PID (RR 1.18, 95% CI 0.89 to 1.55, I² = 72%, 2 RCTs, 243 women, very low-quality evidence), severe PID (RR 1.00, 95% CI 0.96 to 1.05, 1 RCT, 309 women, low-quality evidence), or adverse effects leading to discontinuation of treatment (RR 0.71, 95% CI 0.38 to 1.34, 3 RCTs, 552 women, I² = 0%, low-quality evidence). In a sensitivity analysis limited to a single study at low risk of bias, azithromycin was superior to doxycycline in achieving cure in mild-moderate PID (RR 1.35, 95% CI 1.10 to 1.67, 133 women, moderate-quality evidence). Quinolone versus cephalosporinThere was no clear evidence of a difference between the two drugs in rates of cure for mild-moderate PID (RR 1.04, 95% CI 0.98 to 1.10, 3 RCTs, 459 women, I² = 5%, low-quality evidence), severe PID (RR 1.06, 95% CI 0.91 to 1.23, 2 RCTs, 313 women, I² = 7%, low-quality evidence), or adverse effects leading to discontinuation of treatment (RR 2.24, 95% CI 0.52 to 9.72, 5 RCTs, 772 women, I² = 0%, very low-quality evidence). Nitroimidazole versus no use of nitroimidazoleThere was no conclusive evidence of a difference between the nitroimidazoles (metronidazole) group and the group receiving other drugs with activity over anaerobes (e.g. amoxicillin-clavulanate) in rates of cure for mild-moderate PID (RR 1.01, 95% CI 0.93 to 1.10, 5 RCTs, 2427 women, I² = 60%, moderate-quality evidence), severe PID (RR 0.96, 95% CI 0.92 to 1.01, 11 RCTs, 1383 women, I² = 0%, moderate-quality evidence), or adverse effects leading to discontinuation of treatment (RR 1.00, 95% CI 0.63 to 1.59; participants = 3788; studies = 16; I² = 0% , low-quality evidence). In a sensitivity analysis limited to studies at low risk of bias, findings did not differ substantially from the main analysis (RR 1.06, 95% CI 0.98 to 1.15, 2 RCTs, 1201 women, I² = 32%, high-quality evidence). Clindamycin plus aminoglycoside versus quinoloneThere was no evidence of a difference between the two groups in rates of cure for mild-moderate PID (RR 0.88, 95% CI 0.69 to 1.13, 1 RCT, 25 women, very low-quality evidence), severe PID (RR 1.02, 95% CI 0.87 to 1.19, 2 studies, 151 women, I² = 0%, low-quality evidence), or adverse effects leading to discontinuation of treatment (RR 0.21, 95% CI 0.02 to 1.72, 3 RCTs, 163 women, very low-quality evidence). Clindamycin plus aminoglycoside versus cephalosporinThere was no clear evidence of a difference between the two groups in rates of cure for mild-moderate PID (RR 1.02, 95% CI 0.95 to 1.09, 2 RCTs, 150 women, I² = 0%, low-quality evidence), severe PID (RR 1.00, 95% CI 0.95 to 1.06, 10 RCTs, 959 women, I² = 21%, moderate-quality evidence), or adverse effects leading to discontinuation of treatment (RR 0.78, 95% CI 0.18 to 3.42, 10 RCTs, 1172 women, I² = 0%, very low-quality evidence).

AUTHORS' CONCLUSIONS

We found no conclusive evidence that one regimen of antibiotics was safer or more effective than any other for the cure of PID, and there was no clear evidence for the use of nitroimidazoles (metronidazole) compared to use of other drugs with activity over anaerobes. Moderate-quality evidence from a single study at low risk of bias suggested that a macrolide (azithromycin) may be more effective than a tetracycline (doxycycline) for curing mild-moderate PID. Our review considered only the drugs that are currently used and mentioned by the CDC.

Chlamyweb Study II: a randomised controlled trial (RCT) of an online offer of home-based Chlamydia trachomatis sampling in France

BACKGROUND

The number of cases of Chlamydia trachomatis (Ct) diagnosed has increased in the past 15 years in France as well as in other European countries. This paper reports a randomised controlled trial (RCT) to evaluate whether the offer of home-based testing over the internet increased the number of young people tested for chlamydia compared with the current testing strategy and to estimate the number and risks factors of the infected population. This RCT took place as an element of the Chlamyweb Study-a study aiming to evaluate an intervention (the Chlamyweb Intervention) involving the offer of a free self-sampling kit online to sexually active men and women aged 18-24 years in France.

METHODS

Participants in the Chlamyweb RCT (n=11 075) received either an offer of a free self-sampling kit (intervention group) or were invited to be screened in primary care settings (control group). Risks ratios were used to compare screening rates between the intervention and control groups. Risk factors were analysed for infected people in the intervention group.

RESULTS

The screening frequency was about three times higher among young people who received a self-sampling kit than those who only received a tailored recommendation to be screened (29.2% vs 8.7%). Although rates of screening among men were lower than among women (23.9% vs 33.9%), the intervention effect was greater among men (adjusted risk ratios (aRR)=4.55 vs aRR=2.94). Ct positivity (6.8%) was similar to that observed in STI clinics. It was higher in women (8.3%) than in men (4.4%).

CONCLUSIONS

These results invite us to consider the establishment of a large home-based screening programme, although additional studies including economic assessments are needed to evaluate the most appropriate combination of strategies in the French context.

TRIAL REGISTRAION NUMBER

AFFSAPS n° IDRCB 0211-A01000-41; Results.

Status of vaccine research and development of vaccines for Chlamydia trachomatis infection

Genital infection with Chlamydia trachomatis, a gram-negative obligate intracellular bacterium, is the most common bacterial sexually transmitted infection globally. Ascension of chlamydial infection to the female upper genital tract can cause acute pelvic inflammatory disease, tubal factor infertility, ectopic pregnancy, and chronic pelvic pain. Shortcomings of current chlamydia control strategies, especially for low- and middle-income countries, highlight the need for an effective vaccine. Evidence from animal models, human epidemiological studies, and early trachoma vaccine trials suggest that a C. trachomatis vaccine is feasible. Vaccine development for genital chlamydial infection has been in the preclinical phase of testing for many years, but the first Phase I trials of chlamydial vaccine candidates are underway, and scientific advances hold promise for additional candidates to enter clinical evaluation in the coming years. We describe the clinical and public health need for a C. trachomatis vaccine, provide an overview of Chlamydia vaccine development efforts, and summarize current vaccine candidates in the development pipeline.

The natural history of Chlamydia trachomatis infection in women: a multi-parameter evidence synthesis

BACKGROUND AND OBJECTIVES

The evidence base supporting the National Chlamydia Screening Programme, initiated in 2003, has been questioned repeatedly, with little consensus on modelling assumptions, parameter values or evidence sources to be used in cost-effectiveness analyses. The purpose of this project was to assemble all available evidence on the prevalence and incidence of Chlamydia trachomatis (CT) in the UK and its sequelae, pelvic inflammatory disease (PID), ectopic pregnancy (EP) and tubal factor infertility (TFI) to review the evidence base in its entirety, assess its consistency and, if possible, arrive at a coherent set of estimates consistent with all the evidence.

METHODS

Evidence was identified using 'high-yield' strategies. Bayesian Multi-Parameter Evidence Synthesis models were constructed for separate subparts of the clinical and population epidemiology of CT. Where possible, different types of data sources were statistically combined to derive coherent estimates. Where evidence was inconsistent, evidence sources were re-interpreted and new estimates derived on a post-hoc basis.

RESULTS

An internally coherent set of estimates was generated, consistent with a multifaceted evidence base, fertility surveys and routine UK statistics on PID and EP. Among the key findings were that the risk of PID (symptomatic or asymptomatic) following an untreated CT infection is 17.1% [95% credible interval (CrI) 6% to 29%] and the risk of salpingitis is 7.3% (95% CrI 2.2% to 14.0%). In women aged 16-24 years, screened at annual intervals, at best, 61% (95% CrI 55% to 67%) of CT-related PID and 22% (95% CrI 7% to 43%) of all PID could be directly prevented. For women aged 16-44 years, the proportions of PID, EP and TFI that are attributable to CT are estimated to be 20% (95% CrI 6% to 38%), 4.9% (95% CrI 1.2% to 12%) and 29% (95% CrI 9% to 56%), respectively. The prevalence of TFI in the UK in women at the end of their reproductive lives is 1.1%: this is consistent with all PID carrying a relatively high risk of reproductive damage, whether diagnosed or not. Every 1000 CT infections in women aged 16-44 years, on average, gives rise to approximately 171 episodes of PID and 73 of salpingitis, 2.0 EPs and 5.1 women with TFI at age 44 years.

CONCLUSIONS AND RESEARCH RECOMMENDATIONS

The study establishes a set of interpretations of the major studies and study designs, under which a coherent set of estimates can be generated. CT is a significant cause of PID and TFI. CT screening is of benefit to the individual, but detection and treatment of incident infection may be more beneficial. Women with lower abdominal pain need better advice on when to seek early medical attention to avoid risk of reproductive damage. The study provides new insights into the reproductive risks of PID and the role of CT. Further research is required on the proportions of PID, EP and TFI attributable to CT to confirm predictions made in this report, and to improve the precision of key estimates. The cost-effectiveness of screening should be re-evaluated using the findings of this report.

FUNDING

The Medical Research Council grant G0801947.

Chlamydia trachomatis Genital Infections

Etiology, transmission and protection: Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infection (STI) globally. However, C. trachomatis also causes trachoma in endemic areas, mostly Africa and the Middle East, and is a leading cause of preventable blindness worldwide. Epidemiology, incidence and prevalence: The World Health Organization estimates 131 million new cases of C. trachomatis genital infection occur annually. Globally, infection is most prevalent in young women and men (14-25 years), likely driven by asymptomatic infection, inadequate partner treatment and delayed development of protective immunity. Pathology/Symptomatology: C. trachomatis infects susceptible squamocolumnar or transitional epithelial cells, leading to cervicitis in women and urethritis in men. Symptoms are often mild or absent but ascending infection in some women may lead to Pelvic Inflammatory Disease (PID), resulting in reproductive sequelae such as ectopic pregnancy, infertility and chronic pelvic pain. Complications of infection in men include epididymitis and reactive arthritis. Molecular mechanisms of infection: Chlamydiae manipulate an array of host processes to support their obligate intracellular developmental cycle. This leads to activation of signaling pathways resulting in disproportionate influx of innate cells and the release of tissue damaging proteins and pro-inflammatory cytokines. Treatment and curability: Uncomplicated urogenital infection is treated with azithromycin (1 g, single dose) or doxycycline (100 mg twice daily x 7 days). However, antimicrobial treatment does not ameliorate established disease. Drug resistance is rare but treatment failures have been described. Development of an effective vaccine that protects against upper tract disease or that limits transmission remains an important goal.

Chlamydia sequelae cost estimates used in current economic evaluations: does one-size-fit-all?

BACKGROUND

Current evidence suggests that chlamydia screening programmes can be cost-effective, conditional on assumptions within mathematical models. We explored differences in cost estimates used in published economic evaluations of chlamydia screening from seven countries (four papers each from UK and the Netherlands, two each from Sweden and Australia, and one each from Ireland, Canada and Denmark).

METHODS

From these studies, we extracted management cost estimates for seven major chlamydia sequelae. In order to compare the influence of different sequelae considered in each paper and their corresponding management costs on the total cost per case of untreated chlamydia, we applied reported unit sequelae management costs considered in each paper to a set of untreated infection to sequela progression probabilities. All costs were adjusted to 2013/2014 Great British Pound (GBP) values.

RESULTS

Sequelae management costs ranged from £171 to £3635 (pelvic inflammatory disease); £953 to £3615 (ectopic pregnancy); £546 to £6752 (tubal factor infertility); £159 to £3341 (chronic pelvic pain); £22 to £1008 (epididymitis); £11 to £1459 (neonatal conjunctivitis) and £433 to £3992 (neonatal pneumonia). Total cost of sequelae per case of untreated chlamydia ranged from £37 to £412.

CONCLUSIONS

There was substantial variation in cost per case of chlamydia sequelae used in published chlamydia screening economic evaluations, which likely arose from different assumptions about disease management pathways and the country perspectives taken. In light of this, when interpreting these studies, the reader should be satisfied that the cost estimates used sufficiently reflect the perspective taken and current disease management for their respective context.

Trends in ectopic pregnancy rates following assisted reproductive technologies in the UK: a 12-year nationwide analysis including 160 000 pregnancies

STUDY QUESTION

Have the advancement of assisted reproductive technologies (ART) and changes in the incidence of specific causes of infertility-altered ectopic pregnancy (EP) rates following ART over time in the UK?

SUMMARY ANSWER

EP rates in the UK following IVF/ICSI have progressively decreased, and this appears to be associated with a reduction in the incidence of tubal factor infertility and the increased use of both a lower number of embryos transferred and extended embryo culture.

WHAT IS KNOWN ALREADY

Historically, EP rates following ART are known to have increased over time. However, the impact of progress in ART procedures and changes in both policy and the incidence of specific causes of infertility on the overall EP rate in the UK has yet to be studied.

STUDY DESIGN, SIZE, DURATION

A population-based retrospective analysis was carried out on all pregnancies following ART cycles carried out in the UK between 2000 and 2012 included in the anonymized database of the Human Fertilisation and Embryology Authority.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Overall, 161 967 treatment cycles resulting in a pregnancy were included in the analysis. Among them, 8852 pregnancies occurred after intrauterine insemination (IUI) and 153 115 following IVF/ICSI.

MAIN RESULTS AND THE ROLE OF CHANCE

During this period of 12 years, ∼1.4% (n = 2244) of all pregnancies following ART were an EP. Crude EP rates were significantly higher after IVF/ICSI when compared with following IUI (1.4 versus 1.1%, P = 0.043). The incidence of EP decreased significantly over time for IVF/ICSI cycles [incidence rate ratios (IRR) 0.96 per year, 95% confidence interval (CI) 0.94-0.97], but not after IUI (IRR 0.96 per year, 95% CI 0.91-1.03).Among pregnancies resulting from IVF/ICSI, multivariable logistic regression analysis demonstrated that the major risk factor for EP was the presence of tubal infertility [adjusted odds ratio (aOR) 2.23, 95% CI 1.93-2.58), followed by the increased number of embryos transferred (aOR 1.29 for 2 versus 1 embryo transferred, 95% CI 1.11-1.49; aOR 1.69 for 3 or more versus 1 embryo transferred, 95% CI 1.35-2.11). The use of extended embryo culture to Days 3-4 or 5-7 significantly reduced the risk of EP, when compared with the transfer of early cleavage (Days 1-2) embryos (respectively, aOR 0.85, 95% CI 0.76-0.94; and aOR 0.73, 95% CI 0.63-0.84). Finally, frozen embryo transfer (ET) had no effect on the risk of EP following IVF/ICSI (aOR 0.92, 95% CI 0.76-1.11).

LIMITATIONS, REASONS FOR CAUTION

Owing to the use of this particular registry data, well-established risk factors of EP, such as smoking habits or uterine surgery, could not be assessed.

WIDER IMPLICATIONS OF THE FINDINGS

Our results provide the first evidence of a potential benefit-in terms of the reduction in EP rates-of the implementation of national programmes aiming to reduce the incidence of tubal infertility, such as the National Chlamydia Screening Programme. In addition, campaigns for the widespread introduction of single ET may not only reduce the incidence of multiple pregnancies but also the incidence of EP following IVF/ICSI.

STUDY FUNDING/COMPETING INTERESTS

No funding was obtained for this study, and there are no conflicts of interest to declare.

Narrative review of the barriers and facilitators to chlamydia testing in general practice

As the cornerstone of Australian primary health care, general practice is a setting well suited for regular chlamydia testing but testing rates remain low. This review examines the barriers and facilitators to chlamydia testing in general practice. Six databases--Medline, PubMed, Meditext, PsycInfo, Scopus and Web of Science--were used to identify peer-reviewed publications that addressed barriers and facilitators to chlamydia testing in general practice using the following terms: 'chlamydia test*', 'STI test*' 'general practice', 'primary care', 'family medicine', 'barriers', 'facilitators' and 'enablers' from 1997 until November 2013. Data about the study design and key findings were extracted from the publications. A framework method was used to manage the data and organise publications into three categories -patient, general practitioner, and general practice. Key findings were then classified as a barrier or facilitator. Sixty-nine publications were included, with 41 quantitative studies, 17 qualitative studies, and 11 using mixed methods. Common barriers identified in all three groups included a lack of knowledge, awareness or training, demands on time and workload, and the social context of testing. Facilitators included the normalisation of testing, the use of nurses and other practice staff, education and incentives. Numerous barriers and facilitators to chlamydia testing in general practice have been identified. While the barriers are well studied, many of the facilitators are not as well researched, and highlight areas for further study.

2015 UK national guideline for the management of infection with Chlamydia trachomatis

This guideline offers recommendations on the diagnostic tests, treatment regimens and health promotion principles needed for the effective management of Chlamydia trachomatis genital infection. It covers the management of the initial presentation, as well the prevention of transmission and future infection. The guideline is aimed at individuals aged 16 years and older presenting to healthcare professionals working in departments offering Level 3 care in sexually transmitted infections management within the UK. However, the principles of the recommendations should be adopted across all levels, using local care pathways where appropriate.

Pelvic inflammatory disease in the adolescent: a poignant, perplexing, potentially preventable problem for patients and physicians

PURPOSE OF REVIEW

The present review considers recent pelvic inflammatory disease literature. It remains a difficult condition to accurately diagnose and manage in the adolescent woman. Failure of accurate diagnosis and prompt management leads to complications, including chronic pelvic pain and infertility.

RECENT FINDINGS

Annual chlamydia screening of sexually active adolescents is an important method for early identification of this common cause of this disorder. Youth with positive screens can be lost for treatment if effective follow-up plans are not in place in clinical practice. The intrauterine device is not a risk factor for this condition in adolescents and is a recommended contraceptive device in sexually active adolescent women. A variety of chlamydial antigens are being used to help differentiate lower genital infection from upper genital disorder. Clinicians are not following established protocols for its diagnosis and management.

SUMMARY

Sequelae can be reduced in adolescent women if clinicians continue with regular chlamydia screening in sexually active adolescent women, have a low index of suspicion for pelvic inflammatory disease, carefully follow accepted treatment protocols, and teach youth comprehensive sexuality education including regular condom use. Funded research is needed to develop improved diagnosis and management tools as well as a chlamydia vaccine.

Impact and cost-effectiveness of chlamydia testing in Scotland: a mathematical modelling study

Background

Chlamydia is the most common sexually transmitted bacterial infection in Scotland, and is associated with potentially serious reproductive outcomes, including pelvic inflammatory disease (PID) and tubal factor infertility (TFI) in women. Chlamydia testing in Scotland is currently targeted towards symptomatic individuals, individuals at high risk of existing undetected infection, and young people. The cost-effectiveness of testing and treatment to prevent PID and TFI in Scotland is uncertain.

Methods

A compartmental deterministic dynamic model of chlamydia infection in 15–24 year olds in Scotland was developed. The model was used to estimate the impact of a change in testing strategy from baseline (16.8% overall testing coverage; 0.4 partners notified and tested/treated per treated positive index) on PID and TFI cases. Cost-effectiveness calculations informed by best-available estimates of the quality-adjusted life years (QALYs) lost due to PID and TFI were also performed.

Results

Increasing overall testing coverage by 50% from baseline to 25.2% is estimated to result in 21% fewer cases in young women each year (PID: 703 fewer; TFI: 88 fewer). A 50% decrease to 8.4% would result in 20% more PID (669 additional) and TFI (84 additional) cases occurring annually. The cost per QALY gained of current testing activities compared to no testing is £40,034, which is above the £20,000-£30,000 cost-effectiveness threshold. However, calculations are hampered by lack of reliable data. Any increase in partner notification from baseline would be cost-effective (incremental cost per QALY gained for a partner notification efficacy of 1 compared to baseline: £5,119), and would increase the cost-effectiveness of current testing strategy compared to no testing, with threshold cost-effectiveness reached at a partner notification efficacy of 1.5. However, there is uncertainty in the extent to which partner notification is currently done, and hence the amount by which it could potentially be increased.

Conclusions

Current chlamydia testing strategy in Scotland is not cost-effective under the conservative model assumptions applied. However, with better data enabling some of these assumptions to be relaxed, current coverage could be cost-effective. Meanwhile, increasing partner notification efficacy on its own would be a cost-effective way of preventing PID and TFI from current strategy.

Electronic supplementary material

The online version of this article (doi:10.1186/1742-4682-12-2) contains supplementary material, which is available to authorized users.

The effectiveness of gentamicin in the treatment of Neisseria gonorrhoeae: a systematic review

BACKGROUND

A high level of resistance in Neisseria gonorrhoeae has developed against penicillins, sulphonamides, tetracyclines and quinolones, and recent surveillance data have shown a gradual reduction in sensitivity to current first-line agents with an upward drift in the minimum inhibitory concentration of ceftriaxone. Laboratory sensitivity testing suggests that gentamicin, an aminoglycoside, may be an effective treatment option for gonorrhoea infection when used as a single intramuscular dose.

METHODS

A search of electronic reference databases and grey literature was used to identify randomised trials and well-conducted prospective studies with concurrent controls evaluating single-dose gentamicin against placebo or a comparator regimen in the treatment of uncomplicated gonorrhoea infection in men and women aged 16 years and over. The primary outcome was microbiological cure of N. gonorrhoeae.

RESULTS

Eight hundred and thirty-nine studies were identified, of which five (1,063 total participants) were included. All five studies administered single-dose gentamicin via intramuscular injection to men with uncomplicated gonococcal urethritis. Three studies were randomised trials, one was quasi-randomised and one was non-randomised but included a comparator arm. Comparator antibiotics included an alternative aminoglycoside or antibiotic used in the syndromic management of male urethritis. Methodology was poorly described in all five included studies. The high risk of bias within studies and clinical heterogeneity between studies meant that it was inappropriate to pool data for meta-analysis. Cure rates of 62% to 98% were reported with gentamicin treatment. The relative risk of cure was comparable between gentamicin and comparator antibiotics.

CONCLUSIONS

The studies identified provide insufficient data to support or refute the efficacy and safety of single-dose intramuscular gentamicin in the treatment of uncomplicated gonorrhoea infection. Additional randomised trials to evaluate gentamicin for this indication are therefore required.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42012002490.

An early evaluation of clinical and economic costs and benefits of implementing point of care NAAT tests for Chlamydia trachomatis and Neisseria gonorrhoea in genitourinary medicine clinics in England

Objectives

To estimate the costs and benefits of clinical pathways incorporating a point of care (POC) nucleic acid amplification test (NAAT) for chlamydia and gonorrhoea in genitourinary medicine (GUM) clinics compared with standard off-site laboratory testing.

Method

We simulated 1.2 million GUM clinic attendees in England. A simulation in Microsoft Excel was developed to compare existing standard pathways of management for chlamydia and gonorrhoea with a POC NAAT. We conducted scenario analyses to evaluate the robustness of the model findings. The primary outcome was the incremental cost-effectiveness ratio. Secondary outcomes included the number of inappropriate treatments, complications and transmissions averted.

Results

The baseline cost of using the point of POC NAAT was £103.9 million compared with £115.6 million for standard care. The POC NAAT was also associated with a small increase of 46 quality adjusted life years, making the new test both more effective and cheaper. Over 95 000 inappropriate treatments might be avoided by using a POC NAAT. Patients receive diagnosis and treatment on the same day as testing, which may also prevent 189 cases of pelvic inflammatory disease and 17 561 onward transmissions annually.

Discussion

Replacing standard laboratory tests for chlamydia and gonorrhoea with a POC test could be cost saving and patients would benefit from more accurate diagnosis and less unnecessary treatment. Overtreatment currently accounts for about a tenth of the reported treatments for chlamydia and gonorrhoea and POC NAATs would effectively eliminate the need for presumptive treatment.

Screening juvenile justice-involved females for sexually transmitted infection: a pilot intervention for urban females in community supervision

Little is known about Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) rates in community-supervised juvenile justice-involved (CSJJI) females, or how to best provide screening for sexually transmitted infections in this population. A pilot intervention allowed case managers to offer optional CT/GC screening to CSJJI females during mandated visits. Anonymous satisfaction surveys and discussion groups assessed intervention acceptability. Case managers met with 514 CSJJI females; 102 (20%) agreed to screening and 117 tests were completed. Among those screened, 21 (18%) had CT and 3 (3%) had GC. Intervention feedback from case managers and clients was positive, but there were barriers to recruitment. Lessons learned from this case manager-facilitated intervention may increase the acceptability and effectiveness of future screening methods in this setting.

Risk of pelvic inflammatory disease following Chlamydia trachomatis infection: analysis of prospective studies with a multistate model

Our objective in this study was to estimate the probability that a Chlamydia trachomatis (CT) infection will cause an episode of clinical pelvic inflammatory disease (PID) and the reduction in such episodes among women with CT that could be achieved by annual screening. We reappraised evidence from randomized controlled trials of screening and controlled observational studies that followed untreated CT-infected and -uninfected women to measure the development of PID. Data from these studies were synthesized using a continuous-time Markov model which takes into account the competing risk of spontaneous clearance of CT. Using a 2-step piecewise homogenous Markov model that accounts for the distinction between prevalent and incident infections, we investigated the possibility that the rate of PID due to CT is greater during the period immediately following infection. The available data were compatible with both the homogenous and piecewise homogenous models. Given a homogenous model, the probability that a CT episode will cause clinical PID was 0.16 (95% credible interval (CrI): 0.06, 0.25), and annual screening would prevent 61% (95% CrI: 55, 67) of CT-related PID in women who became infected with CT. Assuming a piecewise homogenous model with a higher rate during the first 60 days, corresponding results were 0.16 (95% CrI: 0.07, 0.26) and 55% (95% CrI: 32, 72), respectively.

Timing of progression from Chlamydia trachomatis infection to pelvic inflammatory disease: a mathematical modelling study

BACKGROUND

Pelvic inflammatory disease (PID) results from the ascending spread of microorganisms from the vagina and endocervix to the upper genital tract. PID can lead to infertility, ectopic pregnancy and chronic pelvic pain. The timing of development of PID after the sexually transmitted bacterial infection Chlamydia trachomatis (chlamydia) might affect the impact of screening interventions, but is currently unknown. This study investigates three hypothetical processes for the timing of progression: at the start, at the end, or throughout the duration of chlamydia infection.

METHODS

We develop a compartmental model that describes the trial structure of a published randomised controlled trial (RCT) and allows each of the three processes to be examined using the same model structure. The RCT estimated the effect of a single chlamydia screening test on the cumulative incidence of PID up to one year later. The fraction of chlamydia infected women who progress to PID is obtained for each hypothetical process by the maximum likelihood method using the results of the RCT.

RESULTS

The predicted cumulative incidence of PID cases from all causes after one year depends on the fraction of chlamydia infected women that progresses to PID and on the type of progression. Progression at a constant rate from a chlamydia infection to PID or at the end of the infection was compatible with the findings of the RCT. The corresponding estimated fraction of chlamydia infected women that develops PID is 10% (95% confidence interval 7-13%) in both processes.

CONCLUSIONS

The findings of this study suggest that clinical PID can occur throughout the course of a chlamydia infection, which will leave a window of opportunity for screening to prevent PID.

Exploring short-term responses to changes in the control strategy for Chlamydia trachomatis

Chlamydia has a significant impact on public health provision in the developed world. Using pair approximation equations we investigate the efficacy of control programmes for chlamydia on short time scales that are relevant to policy makers. We use output from the model to estimate critical measures, namely, prevalence, incidence, and positivity in those screened and their partners. We combine these measures with a costing tool to estimate the economic impact of different public health strategies. Increasing screening coverage significantly increases the annual programme costs whereas an increase in tracing efficiency initially increases annual costs but over time reduces costs below baseline, with tracing accounting for around 10% of intervention costs. We found that partner positivity is insensitive to changes in prevalence due to screening, remaining at around 33%. Whether increases occur in screening or tracing levels, the cost per treated infection increases from the baseline because of reduced prevalence.

Female genital Chlamydia trachomatis infection: where are we heading?

INTRODUCTION

Urogenital infection by Chlamydia trachomatis is the most common bacterial sexually transmitted disease in the world. C. trachomatis is the etiologic agent of several common genital tract syndromes such as urethritis, cervicitis, and pelvic inflammatory disease in women.

MATERIALS AND METHODS

In this review, the pathophysiology of a chlamydial infection as well as diagnosis, therapy and prevention strategies regarding female chlamydial infection are reviewed.

RESULTS

A chlamydial infection results in minimal or even no symptoms in approximately two-thirds of women, remaining therefore clinically apparent and undiagnosed. C. trachomatis infections are of great socioeconomic and public health concern due to the potential for severe long-term consequences in women, including an increased risk of ectopic pregnancy, tubal infertility and chronic pelvic pain. Moreover, if the bacterium is transmitted during labor to a newborn, it can cause ophthalmia neonatorum and atypical neonatal pneumonia. Due to the documented increased risk of morbidity, several national guidelines are available, including a routine screening for young women and screening during pregnancy that is recommended in several countries.

DISCUSSION

A routine screening for young women and screening during pregnancy is recommended in several countries. However, additional prospective studies of the effectiveness of chlamydia screening are warranted and might be feasible within established screening programs. Moreover, the transition from cervicitis to infertility should be also evaluated in future controlled studies to underline the existing evidence. Additionally, there is an urgent need to educate and inform health-care providers about implementation of screening programs to reduce the spread of chlamydial infection. Moreover, awareness and use of screening programs by the public is needed, which requires informational campaigns for the general public using different media. For improved screening strategies and public awareness, novel approaches have to be developed and evaluated. Finally, guidelines should be actively disseminated to all medical practitioners to increase their use in daily practice. Although the major socioeconomic and public health concerns of C. trachomatis infection are recognized, several considerations and additional measures for addressing this increasingly urgent health problem remain.