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1.
Sci Rep ; 10(1): 3884, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127550

RESUMO

Bacterial vaginosis (BV) is associated with HIV acquisition and adverse pregnancy outcomes. Recurrence after metronidazole treatment is high. HIV-negative, non-pregnant Rwandan BV patients were randomized to four groups (n = 17/group) after seven-day oral metronidazole treatment: behavioral counseling only (control), or counseling plus intermittent use of oral metronidazole, Ecologic Femi+ vaginal capsule (containing multiple Lactobacillus and one Bifidobacterium species), or Gynophilus LP vaginal tablet (L. rhamnosus 35) for two months. Vaginal microbiota assessments at all visits included Gram stain Nugent scoring and 16S rRNA gene qPCR and HiSeq sequencing. All interventions were safe. BV (Nugent 7-10) incidence was 10.18 per person-year at risk in the control group, and lower in the metronidazole (1.41/person-year; p = 0.004), Ecologic Femi+ (3.58/person-year; p = 0.043), and Gynophilus LP groups (5.36/person-year; p = 0.220). In mixed effects models adjusted for hormonal contraception/pregnancy, sexual risk-taking, and age, metronidazole and Ecologic Femi+ users, each compared to controls, had higher Lactobacillus and lower BV-anaerobes estimated concentrations and/or relative abundances, and were less likely to have a dysbiotic vaginal microbiota type by sequencing. Inter-individual variability was high and effects disappeared soon after intervention cessation. Lactobacilli-based vaginal probiotics warrant further evaluation because, in contrast to antibiotics, they are not expected to negatively affect gut microbiota or cause antimicrobial resistance.


Assuntos
Lactobacillus/fisiologia , Metronidazol/farmacologia , Microscopia , Probióticos/farmacologia , Análise de Sequência , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/prevenção & controle , Administração Intravaginal , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Feminino , Humanos , Lactobacillus/genética , Metronidazol/administração & dosagem , Pessoa de Meia-Idade , Projetos Piloto , Prevenção Secundária , Adulto Jovem
2.
Lancet Infect Dis ; 19(6): 658-669, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31031172

RESUMO

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.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito/normas , Guias de Prática Clínica como Assunto , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/tratamento farmacológico , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Adulto , Estudos Transversais , Feminino , Humanos , Ruanda/epidemiologia , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Urinárias/epidemiologia
3.
PLoS One ; 13(7): e0201003, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30036385

RESUMO

BACKGROUND: Hormonal contraception has been associated with a reduced risk of vaginal dysbiosis, which in turn has been associated with reduced prevalence of sexually transmitted infections (STIs), including HIV. Vaginal rings are used or developed as delivery systems for contraceptive hormones and antimicrobial drugs for STI and HIV prevention or treatment. We hypothesized that a contraceptive vaginal ring (CVR) containing oestrogen enhances a lactobacilli-dominated vaginal microbial community despite biomass accumulation on the CVR's surface. METHODS: We enrolled 120 women for 12 weeks in an open-label NuvaRing® study at Rinda Ubuzima, Kigali, Rwanda. Vaginal and ring microbiota were assessed at baseline and each ring removal visit by Gram stain Nugent scoring (vaginal only), quantitative PCR for Lactobacillus species, Gardnerella vaginalis and Atopobium vaginae, and fluorescent in situ hybridization to visualize cell-adherent bacteria. Ring biomass was measured by crystal violet staining. RESULTS: Bacterial vaginosis (BV) prevalence was 48% at baseline. The mean Nugent score decreased significantly with ring use. The presence and mean log10 concentrations of Lactobacillus species in vaginal secretions increased significantly whereas those of G. vaginalis and presence of A. vaginae decreased significantly. Biomass accumulated on the CVRs with a species composition mirroring the vaginal microbiota. This ring biomass composition and optical density after crystal violet staining did not change significantly over time. CONCLUSIONS: NuvaRing® promoted lactobacilli-dominated vaginal microbial communities in a population with high baseline BV prevalence despite the fact that biomass accumulated on the rings.


Assuntos
Dispositivos Anticoncepcionais Femininos/efeitos adversos , Dispositivos Anticoncepcionais Femininos/microbiologia , Lactobacillus/fisiologia , Vagina/microbiologia , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/etiologia , Adulto , Biomassa , Células Epiteliais/citologia , Feminino , Humanos , Lactobacillus/citologia , Lactobacillus/efeitos dos fármacos , Estudos Longitudinais , Prevalência , Ruanda , Vagina/citologia , Vagina/efeitos dos fármacos
4.
PLoS One ; 13(6): e0199096, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29912906

RESUMO

BACKGROUND: Introduction of contraceptive vaginal rings (CVRs) could expand the contraceptive method mix reducing the unmet need for family planning in Rwanda, but data on acceptability of CVRs from low and middle-income countries are lacking. METHODS: This study explores acceptability of contraceptive vaginal ring (NuvaRing) use in Kigali, Rwanda using a mixed methods approach. We collected quantitative and qualitative data before, during and after conducting a clinical trial, using Case Report Forms, Interviewer Administered Questionnaires, In Depth Interviews and Focus Group Discussions. We analyzed the data using an existing theoretical framework including product attributes, relationship attributes and sexual encounter attributes as well as the contextual environment. RESULTS: Our data showed that initial worries reduced over time with actual ring use and ring insertions and removals were described as easy. Most women did not feel the ring during daily activities, appreciated the lack of perceived negative side effects and the increased lubrication. Relationship attributes and sexual encounter attributes such as sexual comfort played a significant role in ring acceptability of the participants and their partners. The contextual environment including Rwandan cultural norms around sexuality positively influenced the acceptance of the NuvaRing. Overall satisfaction was high. CONCLUSIONS: Acceptability of the Nuvaring was high among study participants and represents a promising option that could contribute to lowering the unmet need for family planning in Rwanda.


Assuntos
Dispositivos Anticoncepcionais Femininos , Adulto , Comportamento Contraceptivo , Países em Desenvolvimento , Feminino , Grupos Focais , Humanos , Entrevistas como Assunto , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Ruanda , Inquéritos e Questionários
5.
PLoS One ; 13(6): e0197572, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29856848

RESUMO

BACKGROUND: Contraceptive vaginal rings could play a role in expanding the contraceptive method mix and in preparing communities for the introduction of HIV prevention and multipurpose rings. METHODS: We conducted an open label single-centre randomised clinical trial of intermittent versus continuous use of NuvaRing® in Kigali, Rwanda, in 2013-2014. We randomised 120 HIV-negative women 1:1 to intermittent use (three rings with a ring-free week in between rings) or continuous use (four rings without ring-free weeks). Women underwent an interview, counselling, and a speculum examination, and were tested for pregnancy, bacterial vaginosis (BV) by Nugent scoring, yeasts and trichomonads on wet mount, and sexually transmitted infections. FINDINGS: Only one woman withdrew early. Deliberate ring removals were rare, but spontaneous ring expulsions occurred during 14% of ring use periods. There were no incident pregnancies, serious adverse events, serious social harms, or early discontinuations for safety reasons. Systemic side effects were uncommon, and local side effects were not significantly differently distributed between groups except for lower abdominal pain (P = 0.013). The incidence of vaginal yeasts during ring use was high: 22% of intermittent users and 27% of continuous users had incident vaginal yeasts at one or multiple ring removal visits (P = 0.666), and symptomatic vaginal yeast cases were more common in the continuous than intermittent users (P = 0.031). In contrast, mean Nugent scores improved over time in both groups. CONCLUSIONS: Intermittent and continuous NuvaRing® use were safe in Rwandan women and improved Nugent scores over time. However, attention should be paid to ring expulsions and to a potential increased risk of vaginal candidiasis.


Assuntos
Anticoncepcionais/uso terapêutico , Dispositivos Anticoncepcionais Femininos , Desogestrel/análogos & derivados , Etinilestradiol/uso terapêutico , Infecções por HIV/prevenção & controle , Adulto , Anticoncepção , Desogestrel/uso terapêutico , Combinação de Medicamentos , Feminino , Infecções por HIV/virologia , Humanos , Gravidez , Ruanda/epidemiologia , Vagina/fisiopatologia , Vagina/virologia
6.
Dev World Bioeth ; 18(4): 349-356, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-28493445

RESUMO

People enroll in medical research for many reasons ranging from decisions regarding their own or family members' health situation to broader considerations including access to health and financial resources. In socially vulnerable communities the choice to participate is often based on a risk-benefit assessment that goes beyond the medical aspects of the research, and considers the benefits received. In this qualitative study, we examined the motivations of Rwandan women to participate in a non-commercial collaborative research study examining the safety, acceptability, and adherence of a contraceptive vaginal ring in Rwanda juxtaposed with the perceptions of the research within the community. 351 women attended the screening visit, four were excluded because they were not able to complete the assessment of understanding. The remaining participants' ages ranged from 17 to 38 and 80% had primary level of education or below. 120 were enrolled. Findings highlighted motivations for joining the study that were relayed both formally by the clinic (e.g. testing and treatment) and informally by the community including the positive aspects of the ring. There were also some negative rumors circulating regarding the research site, likely from excluded participants who faced potential stigma based on that exclusion. It was understood by most participants that they were enrolled in a research study and participants actively sought out enrollment in the research for a variety of reasons. The experiences demonstrate that although inequalities in access to health care may create conflicting situations around the study, it is possible to form partnerships between a research center and participants/their partners, for research about reproductive health.


Assuntos
Atitude , Pesquisa Biomédica/ética , Participação da Comunidade , Dispositivos Anticoncepcionais , Consentimento Livre e Esclarecido , Motivação , Adolescente , Adulto , Feminino , Humanos , Pesquisa Qualitativa , Saúde Reprodutiva , Sujeitos da Pesquisa , Ruanda , Adulto Jovem
7.
PLoS One ; 12(6): e0178324, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28594946

RESUMO

We investigated the presence, density and bacterial composition of contraceptive vaginal ring biomass and its association with the vaginal microbiome. Of 415 rings worn by 120 Rwandese women for three weeks, the biomass density was assessed with crystal violet and the bacterial composition of biomass eluates was assessed with quantitative polymerase chain reaction (qPCR). The biomass was visualised after fluorescence in situ hybridisation (FISH) and with scanning electron microscopy (SEM). The vaginal microbiome was assessed with Nugent scoring and vaginal biofilm was visualised after FISH. All vaginal rings were covered with biomass (mean optical density (OD) of 3.36; standard deviation (SD) 0.64). Lactobacilli were present on 93% of the rings, Gardnerella vaginalis on 57%, and Atopobium vaginae on 37%. The ring biomass density was associated with the concentration of A. vaginae (OD +0.03; 95% confidence interval (CI) 0.01-0.05 for one log increase; p = 0.002) and of G. vaginalis (OD +0.03; (95% CI 0.01-0.05; p = 0.013). The density also correlated with Nugent score: rings worn by women with a BV Nugent score (mean OD +0.26), and intermediate score (mean OD +0.09) had a denser biomass compared to rings worn by participants with a normal score (p = 0.002). Furthermore, presence of vaginal biofilm containing G. vaginalis (p = 0.001) and A. vaginae (p = 0.005) correlated with a denser ring biomass (mean OD +0.24 and +0.22 respectively). With SEM we observed either a loose network of elongated bacteria or a dense biofilm. We found a correlation between vaginal dysbiosis and the density and composition of the ring biomass, and further research is needed to determine if these relationships are causal. As multipurpose vaginal rings to prevent pregnancy, HIV, and other sexually transmitted diseases are being developed, the potential impact of ring biomass on the vaginal microbiota and the release of active pharmaceutical ingredients should be researched in depth.


Assuntos
Biofilmes/crescimento & desenvolvimento , Dispositivos Anticoncepcionais Femininos , Disbiose/microbiologia , Vagina/microbiologia , Adulto , África , Biomassa , Feminino , Gardnerella vaginalis/patogenicidade , Humanos , Microbiota/fisiologia , Microscopia Eletrônica de Varredura
8.
PLoS One ; 12(2): e0172522, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28241058

RESUMO

Bacterial vaginosis (BV) is a difficult-to-treat recurrent condition in which health-associated lactobacilli are outnumbered by other anaerobic bacteria, such as Gardnerella vaginalis. Certain genotypes of G. vaginalis can produce sialidase, while others cannot. Sialidase is known to facilitate the destruction of the protective mucus layer on the vaginal epithelium by hydrolysis of sialic acid on the glycans of mucous membranes. This process possibly facilitates adhesion of bacterial cells on the epithelium since it has been linked with the development of biofilm in other pathogenic conditions. Although it has not been demonstrated yet, it is probable that G. vaginalis benefits from this mechanism by attaching to the vaginal epithelium to initiate biofilm development. In this study, using vaginal specimens of 120 women enrolled in the Ring Plus study, we assessed the association between the putative G. vaginalis sialidase A gene by quantitative polymerase chain reaction (qPCR), the diagnosis of BV according to Nugent score, and the occurrence of a BV-associated biofilm dominated by G. vaginalis by fluorescence in situ hybridisation (FISH). We detected the putative sialidase A gene in 75% of the G. vaginalis-positive vaginal specimens and found a strong association (p<0.001) between the presence of a G. vaginalis biofilm, the diagnosis of BV according to Nugent and the detection of high loads of the G. vaginalis sialidase A gene in the vaginal specimens. These results could redefine diagnosis of BV, and in addition might guide research for new treatment.


Assuntos
Biofilmes , Gardnerella vaginalis/enzimologia , Neuraminidase/genética , Vagina/microbiologia , Vaginose Bacteriana/enzimologia , Adolescente , Adulto , Feminino , Gardnerella vaginalis/genética , Humanos , Hidrólise , Hibridização in Situ Fluorescente , Microscopia Confocal , Mucosa/microbiologia , Ácido N-Acetilneuramínico/química , Ácidos Nucleicos Peptídicos/química , Reação em Cadeia da Polimerase , Polissacarídeos/química , Ruanda , Adulto Jovem
9.
Sex Transm Infect ; 92(7): 487-491, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26965870

RESUMO

OBJECTIVES: Bacterial vaginosis (BV) is characterised by a change in the microbial composition of the vagina. The BV-associated organisms outnumber the health-associated Lactobacillus species and form a polymicrobial biofilm on the vaginal epithelium, possibly explaining the difficulties with antibiotic treatment. A better understanding of vaginal biofilm with emphasis on Atopobium vaginae and Gardnerella vaginalis may contribute to a better diagnosis and treatment of BV. METHODS: To this purpose, we evaluated the association between the presence of both bacteria by fluorescence in situ hybridisation (FISH) and BV by Nugent scoring in 463 vaginal slides of 120 participants participating in a clinical trial in Rwanda. RESULTS: A bacterial biofilm was detected in half of the samples using a universal bacterial probe. The biofilm contained A. vaginae in 54.1% and G. vaginalis in 82.0% of the samples. A. vaginae was accompanied by G. vaginalis in 99.5% of samples. The odds of having a Nugent score above 4 were increased for samples with dispersed G. vaginalis and/or A. vaginae present (OR 4.5; CI 2 to 10.3). The probability of having a high Nugent score was even higher when a combination of adherent G. vaginalis and dispersed A. vaginae was visualised (OR 75.6; CI 13.3 to 429.5) and highest when both bacteria were part of the biofilm (OR 119; CI 39.9 to 360.8). CONCLUSIONS: Our study, although not comprehensive at studying the polymicrobial biofilm in BV, provided a strong indication towards the importance of A. vaginae and the symbiosis of A. vaginae and G. vaginalis in this biofilm. TRIAL REGISTRATION NUMBER: NCT01796613.

10.
Sex Transm Infect ; 92(6): 430-2, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26474600

RESUMO

OBJECTIVES: We evaluated the performance of an enzymatic point-of-care rapid test for Chlamydia trachomatis (CT) (the BioChekSwab CT Rapid Test, EnZtek Diagnostics, Rio Vista, California, USA), which detects CT's Peptidase 123CBV enzyme and provides a result 15 min after specimen collection. METHODS: Two endocervical swabs, including one BioChekSwab, per person were obtained from 137 women who participated in a reproductive health study in Rwanda. The BioChekSwab was processed according to the manufacturer's instructions. A substrate was squirted over the swab by the study physician immediately after collection, and another reagent was released over the swab tip at arrival in the laboratory. The test was considered positive if a blue colour developed within 2 min. The other regular flocked endocervical swab was processed at the Institute of Tropical Medicine (ITM), Belgium, using a testing algorithm: Abbott RealTime CT/Neisseria gonorrhoeae (NG) assay with the confirmation of positive results by an in-house real-time PCR assay. RESULTS: Of the 137 women, nine were CT positive by the testing algorithm. All nine positive results were missed by the BioChekSwab assay and four false-positive results were obtained. The sensitivity was therefore 0% (95% CI 0% to 33.6%) and the specificity was 96.9% (95% CI 92.2% to 99.1%). CONCLUSIONS: The BioChekSwab Rapid Test, although ISO13485 certified and Conformitée Européenne (CE) labelled, lacked any sensitivity in our setting.


Assuntos
Colo do Útero/microbiologia , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/isolamento & purificação , Sistemas Automatizados de Assistência Junto ao Leito , Esfregaço Vaginal/métodos , Adolescente , Adulto , Infecções por Chlamydia/epidemiologia , Feminino , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Serviços de Saúde Reprodutiva , Ruanda/epidemiologia , Sensibilidade e Especificidade , Esfregaço Vaginal/normas , Adulto Jovem
11.
PLoS One ; 10(8): e0136658, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26305575

RESUMO

Bacterial vaginosis (BV), a condition defined by increased vaginal discharge without significant inflammation, is characterized by a change in the bacterial composition of the vagina. Lactobacillus spp., associated with a healthy vaginal microbiome, are outnumbered by BV-associated organisms. These bacteria could form a polymicrobial biofilm which allows them to persist in spite of antibiotic treatment. In this study, we examined the presence of Gardnerella vaginalis and Atopobium vaginae in vaginal biofilms using Peptide Nucleic Acid (PNA) probes targeting these bacteria. For this purpose, we developed three new PNA probes for A. vaginae. The most specific A. vaginae probe, AtoITM1, was selected and then used in an assay with two existing probes, Gard162 and BacUni-1, to evaluate multiplex FISH on clinical samples. Using quantitative polymerase chain reaction (qPCR) as the gold standard, we demonstrated a sensitivity of 66.7% (95% confidence interval: 54.5% - 77.1%) and a specificity of 89.4% (95% confidence interval: 76.1% - 96%) of the new AtoITM1 probe. FISH enabled us to show the presence of a polymicrobial biofilm in bacterial vaginosis, in which Atopobium vaginae is part of a Gardnerella vaginalis-dominated biofilm. We showed that the presence of this biofilm is associated with high bacterial loads of A. vaginae and G. vaginalis.


Assuntos
Actinobacteria/isolamento & purificação , Biofilmes , Gardnerella vaginalis/isolamento & purificação , Vaginose Bacteriana/microbiologia , Actinobacteria/genética , Actinobacteria/patogenicidade , Feminino , Gardnerella vaginalis/genética , Gardnerella vaginalis/patogenicidade , Humanos , Hibridização in Situ Fluorescente , Sondas de Ácido Nucleico/genética , Ácidos Nucleicos Peptídicos/genética , Vagina/microbiologia , Vaginose Bacteriana/genética , Vaginose Bacteriana/patologia
12.
Clin Chem ; 59(4): 629-40, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23327782

RESUMO

BACKGROUND: Collection of epidemiological data and care of patients are hampered by lack of access to laboratory diagnostic equipment and patients' health records in resource-limited settings. We engineered a low-cost mobile device that combines cell-phone and satellite communication technologies with fluid miniaturization techniques for performing all essential ELISA functions. METHODS: We assessed the device's ability to perform HIV serodiagnostic testing in Rwanda and synchronize results in real time with electronic health records. We tested serum, plasma, and whole blood samples collected in Rwanda and on a commercially available sample panel made of mixed antibody titers. RESULTS: HIV testing on 167 Rwandan patients evaluated for HIV, viral hepatitis, and sexually transmitted infections yielded diagnostic sensitivity and specificity of 100% and 99%, respectively. Testing on 40 Rwandan whole-blood samples-using 1 µL of sample per patient-resulted in diagnostic sensitivity and specificity of 100% and 100%. The mobile device also successfully transmitted all whole-blood test results from a Rwandan clinic to a medical records database stored on the cloud. For all samples in the commercial panel, the device produced results in agreement with a leading ELISA test, including detection of weakly positive samples that were missed by existing rapid tests. The device operated autonomously with minimal user input, produced each result 10 times faster than benchtop ELISA, and consumed as little power as a mobile phone. CONCLUSIONS: A low-cost mobile device can perform a blood-based HIV serodiagnostic test with laboratory-level accuracy and real-time synchronization of patient health record data.


Assuntos
Sorodiagnóstico da AIDS/métodos , Telefone Celular , Área Carente de Assistência Médica , Ensaio de Imunoadsorção Enzimática , Humanos , Miniaturização , Ruanda
13.
Nat Med ; 17(8): 1015-9, 2011 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-21804541

RESUMO

One of the great challenges in science and engineering today is to develop technologies to improve the health of people in the poorest regions of the world. Here we integrated new procedures for manufacturing, fluid handling and signal detection in microfluidics into a single, easy-to-use point-of-care (POC) assay that faithfully replicates all steps of ELISA, at a lower total material cost. We performed this 'mChip' assay in Rwanda on hundreds of locally collected human samples. The chip had excellent performance in the diagnosis of HIV using only 1 µl of unprocessed whole blood and an ability to simultaneously diagnose HIV and syphilis with sensitivities and specificities that rival those of reference benchtop assays. Unlike most current rapid tests, the mChip test does not require user interpretation of the signal. Overall, we demonstrate an integrated strategy for miniaturizing complex laboratory assays using microfluidics and nanoparticles to enable POC diagnostics and early detection of infectious diseases in remote settings.


Assuntos
Doenças Transmissíveis/diagnóstico , Imunoensaio/métodos , Microfluídica/instrumentação , Microfluídica/métodos , Países em Desenvolvimento , Infecções por HIV/diagnóstico , Humanos , Ruanda , Sensibilidade e Especificidade , Sífilis/diagnóstico
14.
PLoS One ; 6(4): e18402, 2011 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-21532753

RESUMO

BACKGROUND: To assess the performance of BED-CEIA (BED) and AxSYM Avidity Index (Ax-AI) assays in estimating HIV incidence among female sex workers (FSW) in Kigali, Rwanda. METHODOLOGY AND FINDINGS: Eight hundred FSW of unknown HIV status were HIV tested; HIV-positive women had BED and Ax-AI testing at baseline and ≥12 months later to estimate assay false-recent rates (FRR). STARHS-based HIV incidence was estimated using the McWalter/Welte formula, and adjusted with locally derived FRR and CD4 results. HIV incidence and local assay window periods were estimated from a prospective cohort of FSW. At baseline, 190 HIV-positive women were BED and Ax-AI tested; 23 were classified as recent infection (RI). Assay FRR with 95% confidence intervals were: 3.6% (1.2-8.1) (BED); 10.6% (6.1-17.0) (Ax-AI); and 2.1% (0.4-6.1) (BED/Ax-AI combined). After FRR-adjustment, incidence estimates by BED, Ax-AI, and BED/Ax-AI were: 5.5/100 person-years (95% CI 2.2-8.7); 7.7 (3.2-12.3); and 4.4 (1.4-7.3). After CD4-adjustment, BED, Ax-AI, and BED/Ax-AI incidence estimates were: 5.6 (2.6-8.6); 9.7 (5.0-14.4); and 4.7 (2.0-7.5). HIV incidence rates in the first and second 6 months of the cohort were 4.6 (1.6-7.7) and 2.2 (0.1-4.4). CONCLUSIONS: Adjusted incidence estimates by BED/Ax-AI combined were similar to incidence in the first 6 months of the cohort. Furthermore, false-recent rate on the combined BED/Ax-AI algorithm was low and substantially lower than for either assay alone. Improved assay specificity with time since seroconversion suggests that specificity would be higher in population-based testing where more individuals have long-term infection.


Assuntos
Sorodiagnóstico da AIDS/métodos , Algoritmos , Infecções por HIV/diagnóstico , Trabalho Sexual , Adulto , Estudos de Coortes , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Reações Falso-Positivas , Feminino , Infecções por HIV/epidemiologia , Humanos , Incidência , Ruanda/epidemiologia
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