Implementation and evaluation of the Presto combined qualitative real-time assay for <i>Chlamydia trachomatis</i> and <i>Neisseria gonorrhoeae</i> in Rwanda.

BackgroundThe Presto combined qualitative real-time assay for Chlamydia trachomatis and Neisseria gonorrhoeae (Presto CT/NG PCR assay) is appealing for developing countries, because it can be used with multiple DNA extraction methods and polymerase chain reaction (PCR) platforms.ObjectivesThe objective of the study was to implement and evaluate the Presto CT/NG PCR assay at the National Reference Laboratory (NRL) in Kigali, Rwanda, where no real-time PCR assays for the detection of C. trachomatis or N. gonorrhoeae were available.MethodsThe Presto CT/NG PCR assay was first evaluated at the Institute of Tropical Medicine (ITM) in Antwerp, Belgium. Next, NRL laboratory technicians were trained to use the assay on their ABI PRISM 7500 real-time PCR instrument and their competencies were assessed prior to trial initiation. During the trial, endocervical swabs were tested at the NRL, with bi-monthly external quality control testing monitored by the ITM. The final NRL results were evaluated against extended gold standard testing at the ITM, consisting of the Abbott m2000 RealTime System with confirmation of positive results by an in-house real-time PCR assay for C. trachomatis or N. gonorrhoeae.ResultsOf the 192 samples analysed using the Presto assay at the NRL, 16 samples tested positive for C. trachomatis and 17 tested positive for N. gonorrhoeae; four of these were infected with both. The sensitivity and specificity of the Presto assay were 93.3% (95% confidence interval [CI]: 68.1% - 99.8%) and 99.4% (95% CI: 96.8% - 100%) for C. trachomatis and 100% (95% CI: 76.8% - 100%) and 98.8% (95% CI: 95.8% - 99.9%) for N. gonorrhoeae.ConclusionC. trachomatis and N. gonorrhoeae testing with the Presto assay was feasible in Kigali, Rwanda, and good performance was achieved.KeywordsqPCR; Chlamydia trachomatis; Neisseria gonorrhoeae

Evaluation of Convalescent Plasma for Ebola Virus Disease in Guinea

: In the wake of the recent outbreak of Ebola virus disease (EVD) in several African countries, the World Health Organization prioritized the evaluation of treatment with convalescent plasma derived from patients who have recovered from the disease. We evaluated the safety and efficacy of convalescent plasma for the treatment of EVD in Guinea. : In this nonrandomized, comparative study, 99 patients of various ages (including pregnant women) with confirmed EVD received two consecutive transfusions of 200 to 250 ml of ABO-compatible convalescent plasma, with each unit of plasma obtained from a separate convalescent donor. The transfusions were initiated on the day of diagnosis or up to 2 days later. The level of neutralizing antibodies against Ebola virus in the plasma was unknown at the time of administration. The control group was 418 patients who had been treated at the same center during the previous 5 months. The primary outcome was the risk of death during the period from 3 to 16 days after diagnosis with adjustments for age and the baseline cycle-threshold value on polymerase-chain-reaction assay; patients who had died before day 3 were excluded. The clinically important difference was defined as an absolute reduction in mortality of 20 percentage points in the convalescent-plasma group as compared with the control group. : A total of 84 patients who were treated with plasma were included in the primary analysis. At baseline, the convalescent-plasma group had slightly higher cycle-threshold values and a shorter duration of symptoms than did the control group, along with a higher frequency of eye redness and difficulty in swallowing. From day 3 to day 16 after diagnosis, the risk of death was 31% in the convalescent-plasma group and 38% in the control group (risk difference, -7 percentage points; 95% confidence interval [CI], -18 to 4). The difference was reduced after adjustment for age and cycle-threshold value (adjusted risk difference, -3 percentage points; 95% CI, -13 to 8). No serious adverse reactions associated with the use of convalescent plasma were observed. : The transfusion of up to 500 ml of convalescent plasma with unknown levels of neutralizing antibodies in 84 patients with confirmed EVD was not associated with a significant improvement in survival. (Funded by the European Union's Horizon 2020 Research and Innovation Program and others; ClinicalTrials.gov number, NCT02342171.).<br/

Implementation and evaluation of the Presto combined qualitative real-time assay for Chlamydia trachomatis and Neisseria gonorrhoeae in Rwanda

Background: The Presto combined qualitative real-time assay for Chlamydia trachomatis and Neisseria gonorrhoeae (Presto CT/NG PCR assay) is appealing for developing countries, because it can be used with multiple DNA extraction methods and polymerase chain reaction (PCR) platforms. Objectives: The objective of the study was to implement and evaluate the Presto CT/NG PCR assay at the National Reference Laboratory (NRL) in Kigali, Rwanda, where no real-time PCR assays for the detection of C. trachomatis or N. gonorrhoeae were available. Methods: The Presto CT/NG PCR assay was first evaluated at the Institute of Tropical Medicine (ITM) in Antwerp, Belgium. Next, NRL laboratory technicians were trained to use the assay on their ABI PRISM 7500 real-time PCR instrument and their competencies were assessed prior to trial initiation. During the trial, endocervical swabs were tested at the NRL, with bi-monthly external quality control testing monitored by the ITM. The final NRL results were evaluated against extended gold standard testing at the ITM, consisting of the Abbott m2000 RealTime System with confirmation of positive results by an in-house real-time PCR assay for C. trachomatis or N. gonorrhoeae. Results: Of the 192 samples analysed using the Presto assay at the NRL, 16 samples tested positive for C. trachomatis and 17 tested positive for N. gonorrhoeae; four of these were infected with both. The sensitivity and specificity of the Presto assay were 93.3% (95% confidence interval [CI]: 68.1% - 99.8%) and 99.4% (95% CI: 96.8% - 100%) for C. trachomatis and 100% (95% CI: 76.8% - 100%) and 98.8% (95% CI: 95.8% - 99.9%) for N. gonorrhoeae. Conclusion: C. trachomatis and N. gonorrhoeae testing with the Presto assay was feasible in Kigali, Rwanda, and good performance was achieved. Keywords: qPCR; Chlamydia trachomatis; Neisseria gonorrhoeae

Targeted point-of-care testing compared with syndromic management of urogenital infections in women (WISH) : a cross-sectional screening and diagnostic accuracy study

BACKGROUND: Sexually transmitted and urogenital infections are typically managed by WHO-recommended syndromic algorithms in resource-poor countries, and presumptively in Europe. However, algorithms for vaginal discharge and lower abdominal pain perform poorly in women. The women's improvement of sexual and reproductive health (WISH) study in Kigali, Rwanda, sought to improve case-finding and infection management in women by introducing point-of-care tests. The main aim was to compare the performance of the WISH algorithms and the WHO vaginal discharge and lower abdominal pain algorithms with gold standard testing. METHODS: This cross-sectional screening and diagnostic accuracy study recruited women aged 18 years or older with or without urogenital symptoms at risk of acquiring sexually transmitted infections in Kigali, Rwanda. Recruitment activities were implemented by study staff with the help of community mobilisers at health centres, pharmacies, markets, women's organisations, and at "umuganda" community meetings. At the study visit, participants had a face-to-face interview that included questions about current urogenital symptoms. Participants were first asked without prompting (spontaneous reporting), followed by questions about 14 specific symptoms (structural reporting). Next, the WISH algorithms were implemented. All participants had point-of-care tests for bacterial vaginosis (vaginal pH of 5·0 or above) and Trichomonas vaginalis (immunoassay) regardless of symptom reporting. Women with a positive risk score had point-of-care tests for Chlamydia trachomatis and Neisseria gonorrhoea (nucleic acid amplification tests). Vulvovaginal candidiasis was treated presumptively. Nucleic acid amplification tests for C trachomatis, N gonorrhoeae, T vaginalis, bacterial vaginosis, and vulvovaginal candidiasis were the gold standard, and all patients provided swabs for these. FINDINGS: Participants were recruited between July 5, 2016, and March 14, 2017. 705 participants were enrolled in the study and completed a study visit, and 51 attended 53 additional visits. Prevalence by gold standard testing was 8·5% for C trachomatis, 7·1% for N gonorrhoeae, 16·1% for T vaginalis, 18·1% for bacterial vaginosis, and 8·6% for vulvovaginal candidiasis. The WISH algorithms identified similar numbers of C trachomatis, N gonorrhoeae, and T vaginalis infections, but much higher numbers of bacterial vaginosis and vulvovaginal candidiasis infections. Compared with gold standard testing, the WISH algorithms had a good sensitivity and high specificity for C trachomatis (sensitivity 71·7%, specificity 100%), N gonorrhoeae (sensitivity 76·0%, specificity 100%), and T vaginalis (sensitivity 68·5%, specificity 97·4%), high sensitivity but low specificity for bacterial vaginosis (sensitivity 95·2%, specificity 41·2%), and moderate sensitivity and specificity for vulvovaginal candidiasis (sensitivity 64·4%, specificity 69·4%). The performance of vaginal pH testing for bacterial vaginosis improved by increasing the cutoff to 5·5, followed by confirmatory testing (sensitivity 73·6%, specificity 100%). The WHO algorithms had moderate sensitivity and poor specificity for all infections compared with gold standard testing: C trachomatis sensitivity 58·3%, specificity 44·7%; N gonorrhoeae sensitivity 66·0%, specificity 45·2%; T vaginalis sensitivity 60·4%, specificity 45·6%; bacterial vaginosis sensitivity 61·6%, specificity 46·0%; and vulvovaginal candidiasis sensitivity 74·6%, specificity 50·6%. Two participants attended additional visits because they had a mild allergic reaction to metronidazole. Staff and participants considered point-of-care testing feasible and acceptable. INTERPRETATION: Point-of-care testing for urogenital infections might improve case-finding and infection management and is feasible in resource-poor settings. Point-of-care tests should be further developed, including those targeting multiple conditions. Additional studies in other populations, including populations with low prevalence of sexually transmitted and urogenital infections, are warranted. FUNDING: European and Developing Countries Clinical Trials Partnership