Pneumocystis Pneumonia After Allogeneic Hematopoietic Cell Transplantation: A Case-Control Study on Epidemiology and Risk Factors on Behalf of the Infectious Diseases Working Party of the European Society for Blood and Marrow Transplantation.

Pneumocystis pneumonia (PCP) is a life-threatening complication after allogeneic hematopoietic cell transplantation (allo-HCT). However, allo-HCT procedures have evolved toward older patients, unrelated donors, and reduced-intensity conditioning, possibly modifying the risks. Polymerase chain reaction (PCR), widely used nowadays, is more sensitive than microscopy diagnostic methods. This study aimed to assess the factors associated with PCP in allo-HCT recipients within 2 years of HCT and managed according to current procedures. This multicenter, nested case-control study included PCP cases diagnosed by PCR, cytology, or immunofluorescence on bronchoalveolar lavage fluid between 2016 and 2018. Two controls per case were selected from the ProMISe registry and matched for the center, transplant date, and underlying disease. Fifty-two cases and 104 controls were included among the 5452 patients who underwent allo-HCT in the participating centers. PCP occurred at a median of 11.5 months after transplantation. The mortality rate was 24% on day 30 after the PCP diagnosis and 37% on day 90. The clinical presentation and mortality rates of the 24 patients diagnosed using only PCR were not different from those diagnosed with microscopy methods. Our study demonstrates a substantial incidence of, and mortality from, PCP, after allogeneic HCT despite well-established prophylactic approaches. In our experience, PCP nowadays occurs later after transplant than previously reported, justifying the prolongation of prophylaxis after six months in many cases. Allo-HCT recipients diagnosed with PCR as the only PCP marker should benefit from specific treatment as for other patients.

A 16-month-long experience of COVID-19 in allogeneic haematopoietic stem cell transplantation recipients: An SFGM-TC multicentre cohort study.

This 16-month-long multicentre retrospective study of 225 allogeneic haematopoietic stem cell transplantation (alloHSCT) recipients with COVID-19 examines risk factors for severity and mortality, describing the successive waves of infections (from March to June 2020 and from August 2020 to June 2021). We confirm the negative role of low respiratory tract disease and immunosuppressive treatment. We highlight significantly lower percentages of severe forms and COVID-19-related mortality during the second wave. Monthly comparative evolution of cases in alloHSCT recipients and in the French population shows a higher number of cases in alloHSCT recipients during the first wave and a decrease from February 2021.

Statin Use and Incidence of Parkinson's Disease in Women from the French E3N Cohort Study.

BACKGROUND: Statins represent candidates for drug repurposing in Parkinson's disease (PD). Few studies examined the role of reverse causation, statin subgroups, and dose-response relations based on time-varying exposures. OBJECTIVES: We examined whether statin use is associated with PD incidence while attempting to overcome the limitations described previously, especially reverse causation. METHOD: We used data from the E3N cohort study of French women (follow-up, 2004-2018). Incident PD was ascertained using multiple sources and validated by experts. New statin users were identified through linked drug claims. We set up a nested case-control study to describe trajectories of statin prescriptions and medical consultations before diagnosis. We used time-varying multivariable Cox proportional hazards regression models to examine the statins-PD association. Exposure indexes included ever use, cumulative duration/dose, and mean daily dose and were lagged by 5 years to address reverse causation. RESULTS: The case-control study (693 cases, 13,784 controls) showed differences in case-control trajectories, with changes in the 5 years before diagnosis in cases. Of 73,925 women (aged 54-79 years), 524 developed PD and 11,552 started using statins in lagged analyses. Ever use of any statin was not associated with PD (hazard ratio [HR] = 0.87, 95% confidence interval [CI] = 0.67-1.11). Alternatively, ever use of lipophilic statins was significantly associated with lower PD incidence (HR = 0.70, 95% CI = 0.51-0.98), with a dose-response relation for the mean daily dose (P-linear trend = 0.02). There was no association for hydrophilic statins. CONCLUSION: Use of lipophilic statins at least 5 years earlier was associated with reduced PD incidence in women, with a dose-response relation for the mean daily dose. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Ability of epidemiological studies to monitor HPV post-vaccination dynamics: a simulation study.

Genital human papillomavirus (HPV) infections are caused by a broad diversity of genotypes. As available vaccines target a subgroup of these genotypes, monitoring transmission dynamics of nonvaccine genotypes is essential. After reviewing the epidemiological literature on study designs aiming to monitor those dynamics, we evaluated their abilities to detect HPV-prevalence changes following vaccine introduction. We developed an agent-based model to simulate HPV transmission in a heterosexual population under various scenarios of vaccine coverage and genotypic interaction, and reproduced two study designs: post-vs.-prevaccine and vaccinated-vs.-unvaccinated comparisons. We calculated the total sample size required to detect statistically significant prevalence differences at the 5% significance level and 80% power. Although a decrease in vaccine-genotype prevalence was detectable as early as 1 year after vaccine introduction, simulations indicated that the indirect impact on nonvaccine-genotype prevalence (a decrease under synergistic interaction or an increase under competitive interaction) would only be measurable after >10 years whatever the vaccine coverage. Sample sizes required for nonvaccine genotypes were >5 times greater than for vaccine genotypes and tended to be smaller in the post-vs.-prevaccine than in the vaccinated-vs.-unvaccinated design. These results highlight that previously published epidemiological studies were not powerful enough to efficiently detect changes in nonvaccine-genotype prevalence.

Comparison of cohort and nested case-control designs for estimating the effect of time-varying drug exposure on the risk of adverse event in the presence of ties.

Cohort and nested case-control (NCC) designs are frequently used in pharmacoepidemiology to assess the associations of drug exposure that can vary over time with the risk of an adverse event. Although it is typically expected that estimates from NCC analyses are similar to those from the full cohort analysis, with moderate loss of precision, only few studies have actually compared their respective performance for estimating the effects of time-varying exposures (TVE). We used simulations to compare the properties of the resulting estimators of these designs for both time-invariant exposure and TVE. We varied exposure prevalence, proportion of subjects experiencing the event, hazard ratio, and control-to-case ratio and considered matching on confounders. Using both designs, we also estimated the real-world associations of time-invariant ever use of menopausal hormone therapy (MHT) at baseline and updated, time-varying MHT use with breast cancer incidence. In all simulated scenarios, the cohort-based estimates had small relative bias and greater precision than the NCC design. NCC estimates displayed bias to the null that decreased with a greater number of controls per case. This bias markedly increased with higher proportion of events. Bias was seen with Breslow's and Efron's approximations for handling tied event times but was greatly reduced with the exact method or when NCC analyses were matched on confounders. When analyzing the MHT-breast cancer association, differences between the two designs were consistent with simulated data. Once ties were taken correctly into account, NCC estimates were very similar to those of the full cohort analysis.

One-month humoral response following two or three doses of messenger RNA coronavirus disease 2019 vaccines as primary vaccination in specific populations in France: first results from the Agence Nationale Recherche contre le Sida (ANRS)0001S COV-POPART cohort.

OBJECTIVES: We aimed to investigate the 1-month humoral response to two or three doses of a messenger RNA coronavirus disease 2019 (COVID-19) vaccine as a primary vaccination regimen in specific populations compared with that in healthy adults. METHODS: Agence Nationale Recherche contre le Sida (ANRS)0001S-COV-POPART (NCT04824651) is a French nation-wide, multi-centre, prospective, observational cohort study assessing the immune response to COVID-19 vaccines routinely administered to 11 sub-groups of patients with chronic conditions and two control groups. Patients and controls who received at least two vaccine doses and whose results 1 month after the second dose were available were included. The humoral response was assessed 1 month after the first, second and third doses (if applicable) based on the percentage of responders (positive for anti-Spike severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] IgG antibodies), geometric means of anti-Spike SARS-CoV-2 IgG antibodies (enzyme-linked immunosorbent assay) and proportion of participants with anti-SARS-CoV-2-specific neutralizing antibodies (in vitro neutralization assay for the original SARS-CoV-2 strain). All analyses were centralized. RESULTS: We included 4091 participants in this analysis: 2979 participants from specific sub-populations and 1112 controls. Only 522 (17.5%) participants from the specific populations received three doses as a primary vaccination regimen. Patients living with human immunodeficiency virus, cancer and diabetes had high percentages of responders after two doses, whereas patients with solid organ transplants, allogeneic hematopoietic stem cell transplants and hypogammaglobulinaemia had the lowest percentage of responders (35.9% [95% CI, 29.2-43.0], 57.4% [95% CI, 48.1-66.3] and 77.1% [95% CI, 65.6-86.3], respectively). In those who received the third dose, the percentage of responders reached 54.2% (95% CI, 42.9-65.2) (vs. 32.3% [95% CI, 16.7-51.4] after 2 doses) among those with solid organ transplants and 73.9% (95% CI, 58.9-85.7) (vs. 56.1% [95% CI, 46.2-65.7] after 2 doses) among those with hematopoietic stem cell transplants. Similar results were found with anti-SARS-CoV-2-specific neutralizing antibodies. CONCLUSIONS: A lower humoral response to COVID-19 vaccines was observed in the specific populations compared with that in the controls. The third dose of this vaccine in the primary regimen had a positive effect on the percentages of patients who developed anti-Spike IgG antibodies and specific neutralizing antibodies.

Pre-exposure prophylaxis with tixagevimab/cilgavimab (AZD7442) prevents severe SARS-CoV-2 infection in recipients of allogeneic hematopoietic stem cell transplantation during the Omicron wave: a multicentric retrospective study of SFGM-TC.

Since the emergence of the Omicron variant of SARS-CoV-2, though considered less virulent, hospitalization and death rates among immunocompromised patients remain high, especially for poor responders to vaccination. We conducted a retrospective multicentric study to evaluate pre-exposure prophylaxis with AZD7442 (tixagevimab/cilgavimab) for preventing COVID-19 in adult allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. Among the 161 patients of our cohort, 22 (14%) contracted COVID-19 after a median follow-up of 105 days, but no severe form was observed. Only one major adverse event was reported: an acute coronary syndrome, resolved without sequelae. Pending randomized controlled trial results, our data support the use of AZD7442 as pre-exposure prophylaxis for COVID-19 during Omicron wave in allo-HSCT patients who failed to develop humoral immunity to vaccination, to prevent severe and potentially lethal forms of SARS-CoV-2 infection.

Identifying Protective Drugs for Parkinson's Disease in Health-Care Databases Using Machine Learning.

BACKGROUND: Available treatments for Parkinson's disease (PD) are only partially or transiently effective. Identifying existing molecules that may present a therapeutic or preventive benefit for PD (drug repositioning) is thus of utmost interest. OBJECTIVE: We aimed at detecting potentially protective associations between marketed drugs and PD through a large-scale automated screening strategy. METHODS: We implemented a machine learning (ML) algorithm combining subsampling and lasso logistic regression in a case-control study nested in the French national health data system. Our study population comprised 40,760 incident PD patients identified by a validated algorithm during 2016 to 2018 and 176,395 controls of similar age, sex, and region of residence, all followed since 2006. Drug exposure was defined at the chemical subgroup level, then at the substance level of the Anatomical Therapeutic Chemical (ATC) classification considering the frequency of prescriptions over a 2-year period starting 10 years before the index date to limit reverse causation bias. Sensitivity analyses were conducted using a more specific definition of PD status. RESULTS: Six drug subgroups were detected by our algorithm among the 374 screened. Sulfonamide diuretics (ATC-C03CA), in particular furosemide (C03CA01), showed the most robust signal. Other signals included adrenergics in combination with anticholinergics (R03AL) and insulins and analogues (A10AD). CONCLUSIONS: We identified several signals that deserve to be confirmed in large studies with appropriate consideration of the potential for reverse causation. Our results illustrate the value of ML-based signal detection algorithms for identifying drugs inversely associated with PD risk in health-care databases. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Contact patterns and HPV-genotype interactions yield heterogeneous HPV-vaccine impacts depending on sexual behaviors: An individual-based model.

Human papillomaviruses are common sexually transmitted infections, caused by a large diversity of genotypes. In the context of vaccination against a subgroup of genotypes, better understanding the role of genotype interactions and human sexual behavior on genotype dynamics is essential. Herein, we present an individual-based model that integrates realistic heterosexual partnership behaviors and simulates interactions between vaccine and non-vaccine genotypes. Genotype interactions were considered, assuming a previous vaccine-genotype infection shortened (competition) or extended (synergy) the duration of a secondary non-vaccine-genotype infection. Sexual behavior determined papillomavirus acquisition and transmission: only 19.5% of active individuals at most 1 partner r during the year, but > 80% of those with ≥ 2 partners, were infected before vaccine introduction. The pre-vaccination situation was consistent with all genotype interaction scenarios. These genotype interactions, despite being undetectable during the pre-vaccination era, markedly impacted genotype prevalence after vaccination started, with a significant increase/decrease of non-vaccine genotypes prevalence for respectively competitive/synergistic interactions. These prevalence changes were more pronounced in individuals with ≤ 3 partners per year (up to 30% of prevalence modification assuming 65% vaccine coverage) but barely visible for individuals with > 3 partners per year (at most 0.30%). Results suggest the presence of genotype interaction, which is consistent with the pre-vaccine situation, may impact the dynamics of non-vaccine genotypes, particularly in less active individuals.

Effective Letermovir Prophylaxis of CMV infection post allogeneic hematopoietic cell transplantation: Results from the French temporary authorization of use compassionate program.

We report the results of the French Temporary Authorization of Use (ATU) compassionate program of letermovir for primary prophylaxis conducted in 21 transplant centers. Patients were CMV seropositive allogeneic hematopoietic cell transplantation recipients and at high risk for CMV infection. Primary prophylaxis was defined as initiation of letermovir between day 0 and day +28 post-transplant. Between November 2017 and January 2019, 96 patients with a median age of 56 years received letermovir and follow-up data were available for 78 patients. The median time from transplant to letermovir initiation was 4 days, and the median duration of exposure to letermovir was 78 days, with 57 patients still on treatment at the cutoff date. Letermovir was temporarily discontinued in 4 patients (5.1%) and stopped in 39 patients (50.0%), in most cases due to planned end of treatment (n = 16, 20.5%). Fifteen patients (19.2%) each presented one positive CMV PCR, in median 13 days after letermovir initiation. Clinically significant CMV infection was reported in 5 patients (6.4%). No CMV disease was reported. At least one adverse drug reaction was reported for 12 patients (15.4%). In this early access program, letermovir was effective with comparable results of the phase 3 study with a low rate of clinically significant CMV infection, including in patients who were at high-risk for CMV infection.

The first wave of COVID-19 in hospital staff members of a tertiary care hospital in the greater Paris area: A surveillance and risk factors study.

INTRODUCTION: Understanding how hospital staff members (HSMs), including healthcare workers, acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the first wave can guide the control measures in the current second wave in Europe. METHODS: From March 5 to May 10, 2020, the Raymond-Poincaré Hospital held a weekday consultation for HSMs for PCR testing. HSMs were requested to complete a questionnaire on their potential exposure to SARS-CoV-2. RESULTS: Of 200 HSMs screened, 70 tested positive for SARS-CoV-2. Ninety-nine HSMs completed the questionnaire of whom 28 tested positive for SARS-CoV-2. In the multivariable analysis, age of ≥44 years (aOR = 5.2, 95% CI [1.4-22.5]) and not systematically using a facemask when caring for a patient (aOR = 13.9, 95% CI [1.8-293.0]) were significantly associated with SARS-CoV-2 infection. Working in a COVID-19-dedicated ward (aOR = 0.7, 95% CI [0.2-3.2]) was not significantly associated with infection. Community-related exposure in and outside the hospital, hospital meetings without facemasks (aOR = 21.3, 95% CI [4.5-143.9]) and private gatherings (aOR = 10, 95% CI [1.3-91.0]) were significantly associated with infection. CONCLUSIONS: Our results support the effectiveness of barrier precautions and highlight in-hospital infections not related to patient care and infections related to exposure in the community. Protecting HSMs against COVID-19 is crucial in fighting the second wave of the epidemic.

Scoring system for clinically significant CMV infection in seropositive recipients following allogenic hematopoietic cell transplant: an SFGM-TC study.

In order to identify cytomegalovirus (CMV)-seropositive patients who are at risk of developing CMV infection following first allogeneic hematopoietic cell transplantation (allo-HCT), we built up a scoring system based on patient/donor characteristics and transplantation modalities. To this end, 3690 consecutive patients were chronologically divided into a derivation cohort (2010-2012, n = 2180) and a validation cohort (2013-2014, n = 1490). Haploidentical donors were excluded. The incidence of first clinically significant CMV infection (CMV disease or CMV viremia leading to preemptive treatment) at 1, 3, and 6 months in the derivation cohort was 13.8%, 38.5%, and 39.6%, respectively. CMV-seropositive donor, unrelated donor (HLA matched 10/10 or HLA mismatched 9/10), myeloablative conditioning, total body irradiation, antithymocyte globulin, and mycophenolate mofetil significantly and independently affected the incidence of 3-month infection. These six factors were selected to build up the prognostic model. Four risk groups were defined: low, intermediate-low, intermediate-high, and high-risk categories, with a 3-month predicted incidence of first clinically significant CMV infection in the derivation cohort of 22.2%, 31.1%, 45.4%, and 56.9%, respectively. This score represents a framework for the evaluation of patients who are at risk of developing clinically significant CMV infection following allo-HCT. Prospective studies using this score may be of benefit in assessing the value of anti-CMV prophylaxis in well-defined patient cohorts.

Allogeneic HCT for adults with B-cell precursor acute lymphoblastic leukemia harboring IKZF1 gene mutations. A study by the Acute Leukemia Working Party of the EBMT.

The presence of IKZF1 gene mutations is associated with poor prognosis of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The goal of this retrospective study was to evaluate outcome of allogeneic hematopoietic cell transplantation (allo-HCT) in this population. Ninety-five patients transplanted in first (n = 75) or second (n = 20) complete remission (CR) from either HLA-matched sibling (n = 32), unrelated (n = 47) or haploidentical (n = 16) donor were included in the analysis. The probabilities of the overall survival (OS) and leukemia-free survival (LFS) at 2 years were 55% and 47%, respectively. Relapse incidence (RI) was 32% while non-relapse mortality (NRM), 21%. The incidence of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD was 34% and 30%, respectively. The probability of GVHD and relapse-free survival (GRFS) was 35%. In a multivariate analysis positive minimal residual disease (MRD) status was associated with decreased chance of LFS (HR = 3.15, p = 0.004) and OS (HR = 2.37, p = 0.049) as well as increased risk of relapse (HR = 5.87, p = 0.003). Disease stage (CR2 vs. CR1) affected all, LFS, OS, GRFS, RI, and NRM. Results of allo-HCT for patients with BCP-ALL and IKZF1 mutations are generally improving, however, individuals with detectable MRD have poor prognosis and require additional intervention prior to transplantation.

Letermovir for Secondary Prophylaxis of Cytomegalovirus Infection and Disease after Allogeneic Hematopoietic Cell Transplantation: Results from the French Compassionate Program.

Letermovir potently inhibits the cytomegalovirus (CMV)-terminase complex. Letermovir primary prophylaxis given for the first 3 months after allogeneic hematopoietic cell transplantation (HCT) has been shown to reduce clinically significant CMV infection and is well tolerated. Until now, only case reports or small retrospective series have been published on the use of letermovir for a secondary prophylaxis (SP) of CMV infection or diseases after HCT. Here we report the outcome of 80 consecutive CMV-seropositive adult patients included in the French compassionate program and who received letermovir as a SP after at least 1 CMV episode (infection or disease) since HCT. Letermovir was initiated at a median of 170 (49 to 1829) days after transplant and given orally for a median of 118 (26 to 396) days at the usual daily dose of 480 mg once daily and adjusted to 240 mg once daily when coadministered with cyclosporine. The donors were seronegative in 53% of the cases. Fifty patients had a current or previous graft-versus-host disease (GVHD) and 14 had experienced CMV disease since transplant. Four (5.5%) patients developed CMV breakthrough infections (n = 1) or diseases (n = 3) after the initiation of letermovir. In 3 of these 4 patients, further investigation of virologic resistance showed a CMV UL56 mutation C325Y or W, conferring the high-level letermovir resistance. One or more adverse reactions were declared by the local investigator in 15 (19%) patients. Only 2 patients stopped letermovir SP because of an adverse reaction (pruritus, 1; cytopenia, 1). In our experience, letermovir given as a SP may prevent a new CMV reactivation in a high-risk patient population and can be administered for several weeks, providing a bridge between the pre-emptive or therapeutic treatment of a CMV episode and CMV-specific immune reconstitution, giving time for tapering immunosuppressants. Prospective studies are required to confirm these results.

Nonoptimal Vaginal Microbiota After Azithromycin Treatment for Chlamydia trachomatis Infection.

We characterized the composition and structure of the vaginal microbiota in a cohort of 149 women with genital Chlamydia trachomatis infection at baseline who were followed quarterly for 9 months after antibiotic treatment. At time of diagnosis, the vaginal microbiota was dominated by Lactobacillus iners or a diverse array of bacterial vaginosis-associated bacteria including Gardnerella vaginalis. Interestingly, L. iners-dominated communities were most common after azithromycin treatment (1 g monodose), consistent with the observed relative resistance of L. iners to azithromycin. Lactobacillus iners-dominated communities have been associated with increased risk of C. trachomatis infection, suggesting that the impact of antibiotic treatment on the vaginal microbiota could favor reinfections. These results provide support for the dual need to account for the potential perturbing effect(s) of antibiotic treatment on the vaginal microbiota, and to develop strategies to protect and restore optimal vaginal microbiota.

Vaginal microbiota composition and association with prevalent Chlamydia trachomatis infection: a cross-sectional study of young women attending a STI clinic in France.

OBJECTIVES: New molecular techniques have allowed describing groups of bacterial communities in the vagina (community state types (CST)) that could play an important role in Chlamydia trachomatis (CT) infection. Our aim was to describe the distribution of CST in a population of young women in France. METHODS: A cross-sectional study was carried out in June 2015 among anonymous young women attending a STI clinic in Bordeaux, France. Participants provided a vaginal sample for CT screening and sociodemographic data. CT was diagnosed using the Aptima-combo 2 transcription-mediated-amplification assay. Vaginal microbiota composition was characterised using 16S rRNA gene amplicon sequencing. RESULTS: Microbiota composition and CT status were available for 132 women. CST dominated by Lactobacillus crispatus (CST-I), L. iners (CST-III) and a diversity of anaerobes (CST-IV) represented 37.1%, 38.6% and 22.0% of the sample, respectively. Twenty-one out of 132 women were CT positive. Proportions of CT-positive women were higher for samples belonging to CST-III (21.6%) and CST-IV (17.2%) than to CST-I (8.2%). CONCLUSIONS: Five CST were found in 132 young women from a STI clinic in France. These CSTs were not significantly associated with CT but higher proportions of CT-positive women were found in CST-III and CST-IV, consistent with a previous study in the Netherlands. Though our study lacked statistical power and was cross-sectional, it is a necessary first step to understand the structure of the vaginal microbiota in French women with or without infection before performing in-depth longitudinal studies.

Early screening for Chlamydia trachomatis in young women for primary prevention of pelvic inflammatory disease (i-Predict): study protocol for a randomised controlled trial.

BACKGROUND: Genital infection with Chlamydia trachomatis (Ct) is the most common bacterial sexually transmitted infection, especially among young women. Mostly asymptomatic, it can lead, if untreated, to pelvic inflammatory disease (PID), tubal factor infertility and ectopic pregnancy. Recent data suggest that Ct infections are not controlled in France and in Europe. The effectiveness of a systematic strategy for Ct screening in under-25 women remains controversial. The main objective of the i-Predict trial (Prevention of Diseases Induced by Chlamydia trachomatis) is to determine whether early screening and treatment of 18- to-24-year-old women for genital Ct infection reduces the incidence of PID over 24 months. METHODS/DESIGN: This is a randomised prevention trial including 4000 eighteen- to twenty-four-year-old sexually active female students enrolled at five universities. The participants will provide a self-collected vaginal swab sample and fill in an electronic questionnaire at baseline and at 6, 12 and 18 months after recruitment. Vaginal swabs in the intervention arm will be analysed immediately for Ct positivity, and participants will be referred for treatment if they have a positive test result. Vaginal swabs from the control arm will be analysed at the end of the study. All visits to general practitioners, gynaecologists or gynaecology emergency departments for pelvic pain or other gynaecological symptoms will be recorded to evaluate the incidence of PID, and all participants will attend a final visit in a hospital gynaecology department. The primary endpoint measure will be the incidence of PID over 24 months. The outcome status (confirmed, probable or no PID) will be assessed by two independent experts blinded to group assignment and Ct status. DISCUSSION: This trial is expected to largely contribute to the development of recommendations for Ct screening in young women in France to prevent PID and related complications. It is part of a comprehensive approach to gathering data to facilitate decision-making regarding optimal strategies for Ct infection control. The control group of this randomised trial, following current recommendations, will allow better documentation of the natural history of Ct infection, a prerequisite to evaluating the impact of Ct screening. Characterisation of host immunogenetics will also allow identification of women at risk for complications. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02904811 . Registered on September 14, 2016. World Health Organisation International Clinical Trials Registry, NCT02904811. AOM, 15-0063 and P150950. Registered on September 26, 2016. A completed Standard Protocol Items : Recommendations for International Trials (SPIRIT) Checklist is available in additional file 1.