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BACKGROUND: Transfusion-transmitted malaria (TTM) is a public health problem in endemic and nonendemic areas. The Brazilian Ministry of Health (MH) requested the development of a nucleic acid amplification test (NAT) for the detection of Plasmodium spp. in public blood centers to increase blood safety. STUDY DESIGN AND METHODS: The new Brazilian NAT kit named NAT PLUS HIV/HBV/HCV/Malaria Bio-Manguinhos was first implemented in HEMORIO, a public blood center in the city of Rio de Janeiro. Since October 1, 2022, this blood center has been testing all its blood donations for malaria in a pool of six plasma samples to detect Plasmodium spp. by real-time polymerase chain reaction (PCR). RESULTS: Since the implementation of the NAT PLUS platform until February 2023, HEMORIO has successfully received and tested 200,277 donations. The platform detected two asymptomatic donors in the city of Rio de Janeiro, which is a nonendemic region for malaria. Our analyses suggested a malaria from the Amazon region caused by Plasmodium vivax, in the first case, while an autochthonous transmission case by Plasmodium malariae was identified in the rural area of Rio de Janeiro state. DISCUSSION: The NAT PLUS platform detects Plasmodium spp. in plasma samples with sensitivity capable of detecting subpatent infections. This is the first time worldwide that a group developed and implemented molecular diagnosis for Plasmodium spp. to be used by public blood centers to avoid TTM.
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Infecciones por VIH , Hepatitis C , Malaria , Humanos , Virus de la Hepatitis B , Donantes de Sangre , Brasil/epidemiología , Malaria/diagnóstico , Malaria/epidemiología , Plasmodium malariae , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiologíaRESUMEN
COVID-19 made explicit the need for rethinking the way in which we conduct testing for epidemic emergencies. During the COVID-19 pandemic, the dependence on centralized lab facilities and resource-intensive methodologies (e.g., RT-qPCR methods) greatly limited the deployment of widespread testing efforts in many developed and underdeveloped countries. Here, we illustrate the development of a simple and portable diagnostic kit that enables self-diagnosis of COVID-19 at home from saliva samples. We describe the development of a do-it-yourself (DIY) incubator for Eppendorf tubes that can be used to conduct SARS-CoV-2 detection with competitive sensitivity and selectivity from saliva at home. In a proof-of-concept experiment, we assembled Eppendorf-tube incubators at our home shop, prepared a single-tube mix of reagents and LAMP primers in our lab, and deployed these COVID-19 detection kits using urban delivery systems (i.e., Rappifavor or Uber) to more than 15 different locations in Monterrey, México. This straightforward strategy enabled rapid and cost-effective at-home molecular diagnostics of SARS-CoV-2 from real saliva samples with a high sensitivity (100%) and high selectivity (87%).
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The failures in Trichomonas vaginalis (TV) infection diagnosis leave more than half of cases unidentified. In this report, urine and vaginal discharge samples were analyzed by wet mount, culture examination, and real-time PCR by Allplex™ (Seegene®) kit, in a population assisted by the Brazilian Public Health System. From 747 samples, 2.81% were positive for TV in wet mount and culture, and 3.88% by Allplex™. Samples kept at - 80 ºC for 22 months did not impair the PCR technique. The sensitivity for wet mount, culture, and Allplex™ was 72, 100, and 100%, respectively. Allplex™ technique showed highest detection of TV.
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Enfermedades de Transmisión Sexual , Vaginitis por Trichomonas , Trichomonas vaginalis , Femenino , Humanos , Trichomonas vaginalis/genética , Vaginitis por Trichomonas/diagnóstico , Vaginitis por Trichomonas/epidemiología , Brasil/epidemiología , Salud Pública , Sensibilidad y Especificidad , Reacción en Cadena en Tiempo Real de la Polimerasa , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiologíaRESUMEN
ABSTRACT Introduction: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. Method: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). Main results: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. Conclusion: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.
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The prompt and accurate identification of the etiological agents of viral respiratory infections is a critical measure in mitigating outbreaks. In this study, we developed and clinically evaluated a novel melting-curve-based multiplex real-time PCR (M-m-qPCR) assay targeting the RNA-dependent RNA polymerase (RdRp) and nucleocapsid phosphoprotein N of SARS-CoV-2, the Matrix protein 2 of the Influenza A virus, the RdRp domain of the L protein from the Human Respiratory Syncytial Virus, and the polyprotein from Rhinovirus B genes. The analytical performance of the M-m-qPCR underwent assessment using in silico analysis and a panel of reference and clinical strains, encompassing viral, bacterial, and fungal pathogens, exhibiting 100% specificity. Moreover, the assay showed a detection limit of 10 copies per reaction for all targeted pathogens using the positive controls. To validate its applicability, the assay was further tested in simulated nasal fluid spiked with the viruses mentioned above, followed by validation on nasopharyngeal swabs collected from 811 individuals. Among them, 13.4% (109/811) tested positive for SARS-CoV-2, and 1.1% (9/811) tested positive for Influenza A. Notably, these results showed 100% concordance with those obtained using a commercial kit. Therefore, the M-m-qPCR exhibits great potential for the routine screening of these respiratory viral pathogens.
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In resource-limited conditions such as the COVID-19 pandemic, on-site detection of diseases using the Point-of-care testing (POCT) technique is becoming a key factor in overcoming crises and saving lives. For practical POCT in the field, affordable, sensitive, and rapid medical testing should be performed on simple and portable platforms, instead of laboratory facilities. In this review, we introduce recent approaches to the detection of respiratory virus targets, analysis trends, and prospects. Respiratory viruses occur everywhere and are one of the most common and widely spreading infectious diseases in the human global society. Seasonal influenza, avian influenza, coronavirus, and COVID-19 are examples of such diseases. On-site detection and POCT for respiratory viruses are state-of-the-art technologies in this field and are commercially valuable global healthcare topics. Cutting-edge POCT techniques have focused on the detection of respiratory viruses for early diagnosis, prevention, and monitoring to protect against the spread of COVID-19. In particular, we highlight the application of sensing techniques to each platform to reveal the challenges of the development stage. Recent POCT approaches have been summarized in terms of principle, sensitivity, analysis time, and convenience for field applications. Based on the analysis of current states, we also suggest the remaining challenges and prospects for the use of the POCT technique for respiratory virus detection to improve our protection ability and prevent the next pandemic.
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COVID-19 , Virus , Humanos , Pruebas en el Punto de Atención , PandemiasRESUMEN
INTRODUCTION: In Brazil, the blood donor screening for hepatitis B virus (HBV) includes laboratory testing for serological (HBsAg and Anti-HBc) and molecular (HBV DNA) markers. This study aims to correlate serology reactive results with HBV DNA detection among blood donors with at least one HBV infection marker detected in a blood bank in northern Brazil. METHOD: A retrospective search for HBV reactive blood donor data from January 2017 to December 2019 was performed. Serological screening was performed by chemiluminescent microparticle immunoassays Architect HBsAg and Architect Anti-HBc, whereas molecular screening was performed by the HBV nucleic acid test (HBV NAT). MAIN RESULTS: A total of 556 HBsAg reactive results were detected, between positive (47.66%) and inconclusive (52.34%). A total of 3,658 Anti-HBc reactive results were detected, between positive (83.71%) and inconclusive (16.29%). None of the inconclusive results were associated with HBV DNA detection. The HBV DNA detection rates were 47.55% among HBsAg positive samples and 4.08% among Anti-HBc positive samples. The signal-to-cutoff (S/CO) ratio median of HBV NAT positive samples was superior in comparison to HBV NAT negative samples (p < 0.0001). The thresholds found to optimize sensitivity and specificity were 404.15 for Architect HBsAg and 7.77 for Architect Anti-HBc. Three blood donors were in the window period and 1 occult HBV infection case was detected. CONCLUSION: High S/CO ratios were more predictive of HBV DNA detection. However, a number of HBV NAT positive samples gave low values, while some HBV NAT negative samples showed high values, reaffirming the significance of molecular testing to enhance transfusion safety.
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INTRODUCTION: To determine whether clinicopathological characteristics can improve the prediction of metastasis to nonsentinel lymph nodes (NSLNs) over the use of only mRNA copy number in sentinel lymph node (SLN) biopsies. METHODS: This was a retrospective, observational study that included a total of 824 patients with T1-3 breast cancer who had clinically negative, ultrasound-negative axilla without evidence of metastasis and who underwent one-step nucleic acid amplification in SLN biopsies. RESULTS: 118 required a complete axillary lymph node dissection (ALNhD). About 35.6% (42/118) had metastases to a NSLN, and 64.4% (76/118) had no metastasis to a NSLN. The ROC curve of the total tumor load (TTL) presented an area under the curve (AUC) of 0.651 (95%; CI: 0.552-0.751). The 7294 copies of CK19 mRNA were established as the optimal cutoff point, with sensitivity: 93%, specificity: 63%, positive predictive value: 44%, and negative predictive value: 91%. By associating the clinicopathological parameters (multicentricity, pooled immunohistochemistry [IHC], and progesterone receptors), the AUC went up to 0.752 (95% CI: 0.663-0.841). CONCLUSIONS: Clinicopathological factors should be considered together with the total CK19 mRNA copy number (the TTL) of the SLNs to improve the predictive capacity of metastatic involvement of the NSLNs.
INTRODUCCIÓN: Nuestro objetivo era determinar si la influencia de las características clínicopatológicas pueden mejorar la predicción de metástasis en los ganglios linfáticos no centinelas (GLNC) a partir de un punto de corte de copias de ARNm determinado en la biopsia del ganglio linfático centinela (GLC). MÉTODOS: Se realizó un estudio observacional retrospectivo incluyendo a un total de 824 pacientes con cáncer de mama T1-3, con axila clínica y ecográficamente negativa para metástasis en los ganglios axilares. Se les practicó una biopsia selectiva del GLC y estudio posterior mediante el método one step nucleic acid amplification (OSNA). RESULTADOS: 118 precisaron una disección completa de los ganglios linfáticos axilares. 35,6% (42/118) tuvieron metástasis en GLNC y 64.4% (76/118) no presentaron metástasis en GLNC. La curva ROC del log de la carga tumoral total (CTT) presentó un área bajo la curva de 0.651 (95%; IC: 0.552-0.751). Se estableció las 7294 copias de ARNm de CK19 como punto de corte óptimo, con sensibilidad: 93%, especificidad: 63%, valor predictivo positivo: 44% y valor predictivo negativo: 91%. Al asociar los parámetros clinicopatológicos (multicentricidad, inmunohistoquímica (IHQ) agrupado y receptores de progesterona) obtenemos un área bajo la curva mejorada de 0.752 (95% intervalo de confianza [IC] 0.663-0.841). CONCLUSIONES: Los factores clinicopatológicos deberían valorarse asociados al corte de copias de ARNm de la CTT de CK19 de los GLCs para mejorar la capacidad predictiva de afectación metastásica en los GLNCs.
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Neoplasias de la Mama , Axila , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Metástasis Linfática/patología , ARN Mensajero , Biopsia del Ganglio Linfático CentinelaRESUMEN
Zika virus (ZIKV) and Chikungunya virus (CHIKV) are arboviruses that cause important viral diseases affecting the world population. Both viruses can produce remarkably similar clinical manifestations, co-circulate in a geographic region, and coinfections have been documented, thus making clinical diagnosis challenging. Therefore, it is urgent to have better molecular techniques that allow a differential, sensitive and rapid diagnosis from body fluid samples. This systematic review explores evidence in the literature regarding the advances in the molecular diagnosis of Zika and Chikungunya in humans, published from 2010 to March 2021. Four databases were consulted (Scopus, PubMed, Web of Science, and Embase) and a total of 31 studies were included according to the selection criteria. Our analysis highlights the need for standardization in the report and interpretation of new promising diagnostic methods. It also examines the benefits of new alternatives for the molecular diagnosis of these arboviruses, in contrast to established methods.
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Resumen: Introducción: el inicio temprano de la antibioticoterapia adecuada en infecciones graves se asocia con reducción de la mortalidad. La identificación precoz del microorganismo es fundamental para realizar un tratamiento dirigido y disminuir la terapéutica inicial inapropiada. Objetivo: valorar la utilidad de una técnica de biología molecular por amplificación de ácidos nucleicos mediante reacción en cadena de polimerasa en tiempo real para diagnóstico microbiológico temprano y adecuación de la antibioticoterapia en pacientes con neumonías graves. Metodología: estudio retrospectivo observacional llevado a cabo en la unidad de cuidados intensivos del Hospital Maciel. Se analizaron muestras respiratorias de pacientes con diagnóstico o sospecha de neumonía. Se compararon los resultados microbiológicos obtenidos por técnicas convencionales y por biología molecular multiplex (panel neumonía). Resultados: se incluyeron 53 muestras obtenidas de 51 pacientes. El multiplex detectó al menos un microorganismo en 38 (71,7%) muestras frente a 30 (56.6%) desarrollos en cultivos tradicionales. La mayoría de las muestras se obtuvieron bajo antibioticoterapia previa (86.8%). El panel neumonía mostró un porcentaje de concordancia positiva combinado de 100% y un porcentaje de concordancia negativa del 94% para la identificación bacteriana en comparación con los métodos microbiológicos tradicionales. En 27 (51%) casos el resultado del panel de neumonía determinó un cambio en la conducta terapéutica. Conclusiones: la técnica de PCR permite la identificación temprana de microorganismos causantes de neumonía optimizando la terapéutica empírica inicial y racionalizando el uso de antimicrobianos. Un panel negativo aleja el planteo de infección respiratoria a gérmenes habituales y permite considerar diagnósticos diferenciales en cuanto a foco y/o etiología.
Summary: Introduction: the early initiation of the adequate antibiotic therapy in severe infections is associated to a reduction in mortality. Early identification of the microorganism is essential to define directed therapy and decrease the initial inadequate treatment. Objective: to assess usefulness of a molecular biology technique by nucleic acid amplification through a polymerase chain reaction in real time for an early microbiological diagnosis and correction of the antibiotic therapy in patients with severe pneumonias. Method: retrospective, observational study conducted in the intensive care unit of Maciel Hospital. The respiratory samples of patients with a diagnosis of pneumonia or suspicious to have pneumonia were analyzed. The microbiological results obtained were compared using conventional techniques and multiplex molecular biology (pneumonia panel). Results: 53 samples obtained from 51 patients were included in the study. Multiplex detected at least one microorganism in 38 (71.7%) samples compared to 30 (56.6%) in traditional cultures. Most samples were obtained under the previous antibiotic therapy (86.8%). The pneumonia panel showed a combined positive agreement percentage of 100% and a negative agreement of 94% for the identification of bacteria when compared to the traditional microbiological methods. In 27 cases (51%) the pneumonia panel results determined changing the therapeutic behavior. Conclusions: the PCR technique allows for the early identification of microorganisms causing pneumonia, thus optimizing initial empirical therapy and rationalizing the use of antibiotics. A negative panel reduces the suspicion of a respiratory infection caused by the usual germs and enables considering differential diagnosis in terms of etiology or cause.
Resumo: Introdução: o início precoce da antibioticoterapia adequada em infecções graves está associado à redução da mortalidade. A identificação precoce do microrganismo é essencial para realizar o tratamento dirigido e reduzir o uso inicial inadequado de antimicrobianos. Objetivo: avaliar a utilidade de uma técnica de biologia molecular para amplificação de ácidos nucleicos por reação em cadeia da polimerase em tempo real para diagnóstico microbiológico precoce e adequação da antibioticoterapia em pacientes com pneumonia grave. Metodologia: estudo observacional retrospectivo realizado na unidade de terapia intensiva do Hospital Maciel. Amostras respiratórias de pacientes com diagnóstico ou suspeita de pneumonia foram analisadas. Os resultados microbiológicos obtidos por técnicas convencionais e por biologia molecular multiplex (painel de pneumonia) foram comparados. Resultados: foram incluídas 53 amostras obtidas de 51 pacientes. O multiplex detectou pelo menos um microrganismo em 38 (71,7%) amostras em comparação com 30 (56,6%) usando culturas tradicionais. A maioria das amostras foi obtida com antibioticoterapia prévia (86,8%). O painel de pneumonia mostrou uma concordância percentual positiva combinada de 100% e uma concordância percentual negativa de 94% para identificação bacteriana em comparação com métodos microbiológicos tradicionais. Em 27 (51%) casos, o resultado do painel de pneumonia determinou mudança no comportamento terapêutico. Conclusões: a técnica de PCR permite a identificação precoce de microrganismos causadores de pneumonia, otimizando a terapia empírica inicial e racionalizando o uso de antimicrobianos. Um painel negativo afasta a suspeita de infecção respiratória pelos germes usuais e permite considerar diagnósticos diferenciais em termos de foco e/ou etiologia.
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Neumonía/microbiología , Neumonía/tratamiento farmacológico , Reacción en Cadena de la Polimerasa Multiplex , Unidades de Cuidados Intensivos , Neumonía/diagnóstico , Cuidados CríticosRESUMEN
The number of SARS-CoV-2 detection tests requested to the laboratories has dramatically increased together with an urgent need to release reliable responses in a very short time. The two options taken into consideration and analyzed in the current study were the point-of-care test (POCT) based on the nucleic acid amplification test (NAAT) and the Antigen (Ag) rapid test. The POCT-NAAT-based assay was compared with a rapid antigen test of nasopharyngeal swab samples. If the specimen tested positive, it was followed by viral load quantification and by the functional assessment of the residual infectivity. When the initial cycle threshold (Ct) was below 20 (100%), and in the range of 20-25 (92%) and of 25-30 (88%), a great concordance between the POCT-NAAT and the Ag test was observed. Moreover, the positivity of the antigen test was well correlated to a successful infection in vitro (78%), with greater concordance when the initial Ct below 20 or above 35 (100%) and in the range 20-25 (83%). Our findings showed that most of the swabs which tested positive using the antigen test were able to infect the cells in vitro, suggesting that probably only these samples hold residual infectivity and therefore an increased risk of virus transmission at the moment of being tested.
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COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Prueba de COVID-19 , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas de Amplificación de Ácido Nucleico , SARS-CoV-2/genética , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Incidence of health care personnel (HCP) with a higher-risk SARS-CoV-2 exposure and subsequent 14-day quarantine period adds substantial burden on the workforce. Implementation of an early return-to-work (RTW) program may reduce quarantine periods for asymptomatic HCP and reduce workforce shortages during the COVID-19 pandemic. METHODS: This observational quality improvement study included asymptomatic HCP of a multi-facility health care system with higher-risk workplace or non-household community SARS-CoV-2 exposure ≤4 days. The program allowed HCP to return to work 8 days after exposure if they remained asymptomatic through day 7 with day 5-7 SARS-CoV-2 nucleic acid amplification test result negative. RESULTS: Between January 4 and June 25, 2021, 384 HCP were enrolled, 333 (86.7%) remained asymptomatic and of these, 323 (97%) tested negative and were early RTW eligible. Mean days in quarantine was 8.16 (SD 2.40). Median day of early RTW was 8 (range 6-9, IQR 8-8). Mean days saved from missed work was 1.84 (SD 0.52). A total of 297 (92%) HCP did RTW ≤10 days from exposure and days saved from missed work was 546.48. CONCLUSIONS: Implementing an HCP early RTW program is a clinical approach for COVID-19 workplace safety that can increase staffing availability, while maintaining a low risk of SARS-CoV-2 transmission.
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COVID-19 , Aprendizaje del Sistema de Salud , COVID-19/prevención & control , Atención a la Salud , Personal de Salud , Humanos , Pandemias , Mejoramiento de la Calidad , Reinserción al Trabajo , SARS-CoV-2RESUMEN
Hepatitis B virus is a highly infectious blood borne microbial pathogen that causes several hepatic complications like liver cirrhosis and hepatocellular carcinoma. Several methods are available for the detection of HBV, but every method has their own merits and demerits, which restrict their use in clinical laboratories. The aim of this present study is the development of rapid, inexpensive, sensitive, and specific loop-mediated isothermal amplification followed by lateral flow device (LFD) for detection of HBV in blood specimens. METHODS: HBV standard plasma panels and donor plasma specimens were used to evaluate the assay. HBV DNA was extracted by using QiAamp DNA Blood Mini Kit. Amplification was carried out at constant temperature 63 °C for 60 min. LAMP end products were analyzed by using ESE LAMP tube scanner, gel electrophoresis, UV-lamp, and lateral flow device. RESULTS: HBV-LAMP-LFD assay revealed sensitivity of 92% (138/150) of HBV positive plasma specimens. Specificity of HBV-LAMP-LFD was calculated 100%. CONCLUSION: Our study concludes that HBV-LAMP-LFD is rapid, easy to use, sensitive, and specific point-of-care diagnostic assay for the detection of hepatitis B virus in blood samples. This assay can be used in resource-limited settings as well as in HBV endemic areas.
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Virus de la Hepatitis B , Hepatitis B , Hepatitis B/diagnóstico , Virus de la Hepatitis B/genética , Humanos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico/métodos , Sensibilidad y EspecificidadRESUMEN
The COVID-19 pandemic has had an enormous impact on economies and health systems globally, therefore a top priority is the development of increasingly better diagnostic and surveillance alternatives to slow down the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In order to establish massive testing and contact tracing policies, it is crucial to have a clear view of the diagnostic options available and their principal advantages and drawbacks. Although classical molecular methods such as RT-qPCR are broadly used, diagnostic alternatives based on technologies such as LAMP, antigen, serological testing, or the application of novel technologies such as CRISPR-Cas for diagnostics, are also discussed. The present review also discusses the most important automation strategies employed to increase testing capability. Several serological-based diagnostic kits are presented, as well as novel nanotechnology-based diagnostic methods. In summary, this review provides a clear diagnostic landscape of the most relevant tools to track COVID-19.
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Tuberculosis (TB) affects around 10 million people worldwide in 2019. Approximately 3.4â% of new TB cases are multidrug-resistant. The gold standard method for detecting Mycobacterium tuberculosis, which is the aetiological agent of TB, is still based on microbiological culture procedures, followed by species identification and drug sensitivity testing. Sputum is the most commonly obtained clinical specimen from patients with pulmonary TB. Although smear microscopy is a low-cost and widely used method, its sensitivity is 50-60â%. Thus, owing to the need to improve the performance of current microbiological tests to provide prompt treatment, different methods with varied sensitivity and specificity for TB diagnosis have been developed. Here we discuss the existing methods developed over the past 20 years, including their strengths and weaknesses. In-house and commercial methods have been shown to be promising to achieve rapid diagnosis. Combining methods for mycobacterial detection systems demonstrates a correlation of 100â%. Other assays are useful for the simultaneous detection of M. tuberculosis species and drug-related mutations. Novel approaches have also been employed to rapidly identify and quantify total mycobacteria RNA, including assessments of global gene expression measured in whole blood to identify the risk of TB. Spoligotyping, mass spectrometry and next-generation sequencing are also promising technologies; however, their cost needs to be reduced so that low- and middle-income countries can access them. Because of the large impact of M. tuberculosis infection on public health, the development of new methods in the context of well-designed and -controlled clinical trials might contribute to the improvement of TB infection control.
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BACKGROUND: Accurate and rapid diagnosis of Clostridium difficile infection (CDI) is critical for effective patient management and implementation of infection control measures to prevent transmission. OBJECTIVES: We updated our previous meta-analysis to provide a more reliable evidence base for the clinical diagnosis of Xpert C. difficile (Xpert C. difficile) assay. METHODS: We searched PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), and the Chinese Biomedical Literature Database (CBM) databases to identify studies according to predetermined criteria. STATA 13.0 software was used to analyze the tests for sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curves (AUC). QUADAS-2 was used to assess the quality of included studies with RevMan 5.2. Heterogeneity in accuracy measures was tested with Spearman correlation coefficient and chi-square. Meta-regressions and subgroup analyses were performed to figure out the potential sources of heterogeneity. Model diagnostics were used to evaluate the veracity of the data. RESULTS: A total of 26 studies were included in the meta-analysis. The pooled sensitivity (95% confidence intervals [CI]) for diagnosis was 0.97(0.95-0.98), and specificity was 0.96(0.95-0.97). The AUC was 0.99 (0.98-1.00). Model diagnostics confirmed the robustness of our meta-analysis's results. Significant heterogeneity was still observed when we pooled most of the accuracy measures of selected studies. Meta-regression and subgroup analyses showed that the sample size and type, ethnicity, and disease prevalence might be the conspicuous sources of heterogeneity. CONCLUSIONS: The up-to-date meta-analysis showed the Xpert CD assay had good accuracy for detecting CDI. However, the diagnosis of CDI must combine clinical presentation with diagnostic testing to better answer the question of whether the patient actually has CDI in the future, and inclusion of preanalytical parameters and clinical outcomes in study design would provide a more objective evidence base.
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Clostridioides difficile , Infecciones por Clostridium , Pruebas Diagnósticas de Rutina , Clostridioides difficile/genética , Infecciones por Clostridium/diagnóstico , Pruebas Diagnósticas de Rutina/normas , Humanos , Curva ROC , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Availability of several commercial tests with different Clostridioides difficile targets contributes to uncertainty and controversies around the optimal diagnostic algorithm. While numerous studies have estimated the financial impact of C. difficile infection, models to guide testing strategies decisions in developing countries, where economic value significantly impacts clinical practice, are currently not available. AIM: To determine the cost of illness of different C. difficile infection (CDI) diagnostic strategies in developing countries. METHODS: Cost-comparison analysis was performed to compare eleven different algorithms of CDI diagnosis. The basis of calculation was a hypothetical cohort of 1000 adult inpatients suspected of CDI. We analyzed turnaround time of test results (i.e., time from taking sample to results emission), test performance (i.e., sensitivity and specificity) and testing costs. Patients were divided in true positive, false positive, true negative and false negative in order to integrate test performance and economics effects. Additional medical costs were calculated: costs of hygiene, medication, length of stay and intensive care unit costs, based on a Brazilian University Hospital costs. CDI prevalence was considered 22.64%. FINDINGS: From laboratory-assisted tests, simultaneous glutamate dehydrogenase (GDH) and toxin A/B rapid immunoassay arbitrated by nucleic acid amplification test (NAAT) presented the lowest cost of illness (450,038.70 USD), whereas standalone NAAT had the highest (523,709.55 USD). Empirical diagnosis only presented the highest overall cost (809,605.44 USD). CONCLUSION: The two-step algorithm with simultaneous GDH and toxin A/B rapid immunoassay arbitrated by NAAT seems to be the best strategy for CDI diagnosis in developing countries.
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Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/economía , Inmunoensayo/economía , Técnicas de Amplificación de Ácido Nucleico/economía , Algoritmos , Antibacterianos/economía , Antibacterianos/uso terapéutico , Proteínas Bacterianas/genética , Toxinas Bacterianas/análisis , Brasil , Clostridioides difficile/genética , Clostridioides difficile/fisiología , Infecciones por Clostridium/tratamiento farmacológico , Infecciones por Clostridium/microbiología , Costo de Enfermedad , Países en Desarrollo/economía , Reacciones Falso Negativas , Glutamato Deshidrogenasa/genética , Humanos , Inmunoensayo/métodos , Técnicas de Amplificación de Ácido Nucleico/métodosRESUMEN
We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015-2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens.
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Complicaciones Infecciosas del Embarazo , Infección por el Virus Zika , Virus Zika , Brotes de Enfermedades , Femenino , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Puerto Rico , Infección por el Virus Zika/epidemiologíaRESUMEN
Chlamydia and gonorrhea are common sexually transmitted infections (STIs) that can cause multiple problems, and can be easily treated, but frequently present without symptoms. Because of this, commonly used syndromic diagnosis misses a majority of infected persons. Previously, diagnostic tests were expensive and invasive, but newer nucleic-acid amplification tests (NAATs) are available that use urine to non-invasively test for these infections. These analyses used data from seroprevalence studies conducted in five militaries. Data included self-reported current symptoms of STIs as well as chlamydia and gonorrhea NAAT results. A total of 4923 men were screened for chlamydia and gonorrhea from these 5 militaries during April 2016 to October 2017. The combined prevalence of chlamydia and gonorrhea in these five militaries ranged from 2.3% in Burundi to 11.9% in Belize. These infections were not successfully identified by symptomology; for example, only 2% of cases in Belize reported symptoms. In three of the five countries there was no statistical association between symptoms and positive NAAT results. The majority of individuals with these infections (81% to 98%) would be undiagnosed and untreated using only symptomology. Therefore, using symptoms alone to diagnose cases of chlamydia and gonorrhea is not an effective way to control these infections. We propose that automated, cartridge-based NAATs, be considered for routine use in diagnosing those at risk for STIs.
Asunto(s)
Infecciones por Chlamydia/epidemiología , Gonorrea/epidemiología , Técnicas de Amplificación de Ácido Nucleico , Asunción de Riesgos , Enfermedades de Transmisión Sexual/diagnóstico , Adolescente , Adulto , Anciano , Belice/epidemiología , Benin/epidemiología , Burundi/epidemiología , Infecciones por Chlamydia/diagnóstico , Infecciones por Chlamydia/transmisión , Chlamydia trachomatis/genética , Chlamydia trachomatis/inmunología , Chlamydia trachomatis/aislamiento & purificación , Pruebas Diagnósticas de Rutina/métodos , República Dominicana/epidemiología , Ghana/epidemiología , Gonorrea/diagnóstico , Gonorrea/transmisión , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Instalaciones Militares/estadística & datos numéricos , Personal Militar/estadística & datos numéricos , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/inmunología , Neisseria gonorrhoeae/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Estudios Seroepidemiológicos , Conducta Sexual/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/microbiología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: In low transmission settings early diagnosis is the main strategy to reduce adverse outcomes of malaria in pregnancy; however, microscopy and rapid diagnostic tests (RDTs) are inadequate for detecting low-density infections. We studied the performance of the highly sensitive-RDT (hsRDT) and the loop mediated isothermal DNA amplification (LAMP) for the detection of P. falciparum in pregnant women. METHODS: A cross-sectional study was conducted in two malaria-endemic municipalities in Colombia. We screened pregnant women in the context of an antenatal care program in health facilities and evaluated five tests (microscopy, conventional RDT, hsRDT, LAMP and nested polymerase chain reaction-PCR) for the detection of P. falciparum in peripheral blood, using a quantitative reverse transcription PCR (qRT-PCR) as the reference standard. Diagnostic performance of hsRDT and LAMP were compared with routine testing. RESULTS: The prevalence of P. falciparum was 4.5% by qRT-PCR, half of those infections were subpatent. The sensitivity of the hsRDT (64.1%) was slightly better compared to microscopy and cRDT (59 and 53.8% respectively). LAMP had the highest sensitivity (89.7%) for detecting P. falciparum and the ability to detect very low-density infections (minimum parasite density detected 0.08 p/µL). CONCLUSIONS: There is an underestimation of Plasmodium spp. infections by tests routinely used in pregnant women attending antenatal care visits. LAMP methodology can be successfully implemented at local hospitals in malaria-endemic areas. The relevance of detecting and treating this sub-patent P. falciparum infections in pregnant women should be evaluated. TRIAL REGISTRATION: ClinicalTrials.gov, Identifier: NCT03172221 , Date of registration: May 29, 2017.