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BACKGROUND: Ringworm is highly prevalent in our setting and is frequently observed in our routine clinical practice. Diagnostic confirmation depends on techniques that are not always accessible (PCR), with highly variable sensitivity depending on the observer (direct microscopy) or delayed results (culture, histopathology). Recently, an immunochromatography-based rapid test (Diafactory®) for the antigenic detection of dermatophytes has been developed. This diagnostic tool can help diagnose ringworm, allowing early initiation of treatment and fewer consultation visits. OBJECTIVE: To determine the sensitivity and specificity of the rapid antigen detection test compared to conventional culture. MATERIAL AND METHODS: For a full year, 333 nail samples were collected from patients with suspected onychomycosis. The rapid test and the conventional culture were simultaneously performed on each sample. Those with a positive antigenic test result began treatment early. The remaining patients had appointments for serial cultures and subsequent medical consultation to evaluate the results. RESULTS: Compared to conventional culture, the sensitivity and specificity rates of the rapid antigen detection test are 97.2% and 80.7%, respectively. CONCLUSION: The effectiveness of the rapid antigen detection test is similar to that of conventional culture for the detection of dermatophytes in nail samples. It is a quick and simple diagnostic technique that reduces the number of patient visits to the hospital, and allows early treatment start.
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INTRODUCTION: Pneumococcal bacteraemia is a major contributor to global morbidity and mortality. Traditional culture-based methods lack sensitivity and are time-consuming. This study aimed to assess the effectiveness of two culture-independent assays, the MALDI-TOF-MS Sepsityper® module and the lateral flow inmunochromatography test (LFICT) with the Standard F® Streptococcus pneumoniae, directly from positive blood culture (BC) bottles. METHODS: A prospective study was conducted from December 2021 to July 2022. For all BC positives for S. pneumoniae a double centrifugation protocol was implemented. The resulting pellet was subsequently processed using both techniques. RESULTS: The LFICT showed exceptional performance with 100% sensitivity and specificity, outperforming the MALDI-TOF-MS Sepsityper® module, which achieved 85.2% sensitivity and 100% specificity. Nevertheless, the combination of these assays offers a robust and comprehensive approach to diagnosis. CONCLUSIONS: The simultaneous use of both techniques offers a promising alternative that can be integrated into routine practices directly from BC samples.
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Bacteriemia , Infecções Pneumocócicas , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Streptococcus pneumoniae , Humanos , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Estudos Prospectivos , Infecções Pneumocócicas/diagnóstico , Infecções Pneumocócicas/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Streptococcus pneumoniae/isolamento & purificação , Hemocultura/instrumentação , Hemocultura/métodos , Cromatografia de Afinidade/métodos , Cromatografia de Afinidade/instrumentação , Técnicas Bacteriológicas/métodosRESUMO
INTRODUCTION: In order to deal with the current pandemic caused by the novel SARS-CoV-2 coronavirus several serological immunoassays have been recently developed with the objective of being used as a complementary diagnostic tool and to support the RT-PCR technique currently considered the "gold-standard" method. However, these new assays need to be evaluated and validated. The purpose of this study was to assess the performance of five immunoassays (two ELISA and three CLIA assays) and one rapid immunochromatographic test for the detection of anti-SARS-CoV-2 antibodies. METHODS: Five semiquantitative immunoassays (MENARINI®, PALEX®, VIRCLIA®, ROCHE® and SIEMENS®) and one lateral flow rapid test (WONDFO®) were performed. A total of 124 samples were studied. Case serum samples (n=78) were obtained from COVID-19 patients confirmed by real-time RT-PCR/epidemiological-clinical-radiological criteria, and control non-SARS-CoV-2 samples (n=46) belonged to healthy healthcare workers involved in a seroprevalence study. RESULTS: Overall, the tests showed sensitivities around 70-90% and specificities greater than 95%, including the immunochromatographic test. In addition, we observed very good agreements among them, being better for the detection of IgG than for IgM antibodies (Cohen's kappa index of 0.95 for VIRCLIA® IgG with ROCHE®), as well as good diagnostic power of the tests as determined by the ROC curves. CONCLUSIONS: This study demonstrates the proper performance of the different immunoassays in order to be applied in the clinical practice as support in the diagnostic approach and in the development of vaccines and seroepidemiological studies of COVID-19.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Estudos Soroepidemiológicos , Imunoglobulina G , Sensibilidade e Especificidade , Anticorpos Antivirais , Imunoensaio/métodos , Cromatografia de AfinidadeRESUMO
Resumen Los virus de inmunodeficiencia y leucemia felina representan un problema de gran envergadura para los felinos domésticos debido a la multiplicidad de sintomatologías que manifiestan. El objetivo del presente estudio fue establecer, retrospectivamente, la prevalencia en la presentación de ViLeF y VIF en pacientes de seis clínicas de pequeños animales en Bogotá y Chía, en relación con factores como su edad, raza y género. Se realizó un estudio transversal y retrospectivo, mediante la recopilación de datos de 1.014 historias clínicas de pacientes felinos que ingresaron a seis clínicas de la ciudad de Bogotá y Chía, para determinar la prevalencia de VIF y ViLeF y la asociación de estas con factores como edad, género y raza, entre 2015 y 2019, a través de la prueba OR. La detección de los virus se realizó mediante una prueba rápida basada en inmunocromatografía. La mayor prevalencia para cada enfermedad por año fue: 12,3% para VIF en 2012 y 18% para ViLeF en 2019. Los machos presentaron mayores seroprevalencias para ambas enfermedades durante la mayoría los años evaluados. Factores como raza (criolla: VIF: 1,85; ViLeF: 2,01), género (macho: VIF: 1,53 OR; ViLeF: 1,64) y edad (> 7 años: VIF: 3,82; ViLeF: 3,21) se relacionaron positivamente con la presentación de ambas enfermedades en la población felina evaluada.
Abstract Immunodeficiency virus and feline leukemia virus represent major problems for domestic felines due to the multiplicity of symptoms they manifest. The objective of the present study was to establish, retrospectively, the prevalence in the presentation of FeLV and FIV in patients from six small animal clinics in Bogota and Chia, related to factors such as age, race, and gender. A cross-sectional and retrospective study was carried out, collecting data from 1.014 clinical records of feline patients who were admitted to six clinics in the city of Bogota and Chia, to determine the prevalence of FIV and FeLV and their association with factors such as age, gender, and race, between 2015 and 2019 through the OR test. The detection of the viruses was carried out through a rapid test based on immunochromatography. The highest prevalence for each disease per year was 12,3% for FIV in 2012 and 18% for FeLV in 2019. Males presented higher seroprevalences for both diseases during most of the years evaluated. Factors such as race (Creole: FIV: 1,85; FeLV: 2,01), gender (male: FIV: 1.53 OR, FeLV: 1,64), and age (> 7 years: FIV: 3.82; FeLV: 3.21) were positively related to the presentation of both diseases in the feline population evaluated.
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Animais , Gatos , Vírus , Ensaio de Imunoadsorção Enzimática , Leucemia , Doença Crônica , Doença , Cromatografia de Afinidade , Vírus da Imunodeficiência Felina , Vírus da Leucemia Felina , Diagnóstico , Retroviridae , Hospitais VeterináriosRESUMO
RESUMEN La leucemia viral felina (ViLeF) es una enfermedad retroviral letal, de una elevada prevalência en Colombia, que afecta a felinos de diferentes edades y sexos. El objetivo de esta investigación fue determinar la frecuencia por serodiagnóstico de ViLeF en felinos del centro integral de bienestar animal Ceiba, ubicado en Rionegro, Antioquia (Colombia), en 2020. Para ello, se realizó un estudio descriptivo longitudinal de serofrecuencia de ViLeF desde enero hasta diciembre de 2020. Fueron muestreados 92 gatos, a los cuales se les efectuó una prueba p27 por inmunoensayo comercial Elisa (Idexx©, Snap Combo Plus®, Maine, EE. UU.). La frecuencia de felinos positivos fue 30/92 (32,60%) y el mes de mayo fue el de mayor frecuencia (9,78%). Los machos positivos fueron 17/92 (18,47%) y las hembras 13/92 (14,13%). La edad promedio de seropositividad fue 2,14 años. La frecuencia de ViLeF en 2020 para Ceiba, Rionegro (Colombia) es de 32,60%, un valor elevado con respecto a descripciones en otros albergues para felinos. ViLeF es una enfermedad que está siendo reportada con mayor frecuencia en Colombia, debido a que las medidas de prevención no se están adoptando rutinariamente.
ABSTRACT Feline viral leukemia (ViLeF) is a lethal retroviral disease with a high prevalence in Colombia that affects felines of different ages and sexes. The purpose of this investigation was to determine the frequency by serodiagnosis of ViLeF in felines of the integral center of animal welfare Ceiba, located in Rionegro, Antioquia (Colombia), during 2020. For that, a longitudinal descriptive study of ViLeF serofrequency from were made January to December 2020. 92 cats were sampled, which were tested for p27 by commercial Elisa immunoassay (Idexx©, Snap Combo Plus®, Maine, USA). The frequency of positive felines was 30/92 (32,60%). May was the month with the highest frequency (9,78%). The positivity frequency for males was 17/92 (18,47%) and the frequency for females 13/92 (14,13%). The main age of seropositivity was 2,14 years. The frequency of ViLeF in 2020 for Ceiba, Rionegro (Colombia) is 32,60%. This is a high value in comparison to descriptions in other shelters for felines. ViLeF, in Colombia, is a disease that has been reported with more frequency because prevention measures are not being adopted routinely.
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Animais , Gatos , Ensaio de Imunoadsorção Enzimática , Morbidade , Cromatografia de Afinidade , Leucemia Felina , Vírus da Leucemia Felina , Felidae , Imunoensaio , Testes Sorológicos , Doença , PrevalênciaRESUMO
INTRODUCTION AND AIMS: Viral hepatitis, which appears most frequently at birth or during childhood, is a disease whose transmission routes include tears, bile, sexual fluids, sweat, milk, urine, feces, and saliva. The aim of the present study was to analyze the specificity of the immunochromatographic and ELISA diagnostic tests for hepatitis B surface antigen and compare them with PCR testing. MATERIALS AND METHODS: The study sample was made up of 140 men and 60 women referred to the Urmia Medical University hospital to undergo PCR testing for HBV diagnosis. The ELISA test was performed using the Pioneer Medicine Company kit (Tehran, Iran). RESULTS: The results of the HBs-Ag rapid test and the ELISA test were compared with the PCR test. The HBs-Ag rapid test had 97% sensitivity and 91% specificity, whereas the ELISA test had 78% sensitivity and 76% specificity. DISCUSSION AND CONCLUSION: According to our results, the immunochromatographic test was accurate for diagnosing HBs-Ag in blood and the ELISA test had acceptable sensitivity and specificity, compared with PCR testing.
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Antígenos de Superfície da Hepatite B , Hepatite B , Cromatografia de Afinidade , Testes Diagnósticos de Rotina , Ensaio de Imunoadsorção Enzimática , Feminino , Hepatite B/diagnóstico , Vírus da Hepatite B/genética , Humanos , Recém-Nascido , Irã (Geográfico) , Masculino , Reação em Cadeia da PolimeraseRESUMO
Resumen Un diagnóstico rápido y seguro de la infección por Trypanosoma cruzi permite la administración inmediata de un tratamiento etiológico específico, en los casos clínicamente manifiestos. En el presente trabajo, en 100 sueros de pacientes con diagnóstico presuntivo de infección por T. cruzi, se evaluó el desempeño de la prueba rápida Chagas Ab Rapid SD Bioline (PDR) para el diagnóstico serológico, se la comparó con el estándar diagnóstico (par serológico) y se la valoró para su empleo en la rutina del laboratorio. La PDR reveló un índice de concordancia muy bueno respecto del estándar diagnóstico (Kappa=0,989 [IC95% 0,965-1,000]) y los parámetros de sensibilidad, especificidad, valores predictivos positivos y negativos revelaron un buen desempeño. El índice de Youden informó un buen rendimiento de la prueba (J=0,98 [IC95% 0,93-1,02]); y en el mismo sentido, tanto la razón de verosimilitud positiva (RV (+)= infinito), como la negativa (RV (-)= 0,02 [IC95% 0,00-0,16]), mostraron aumentada la probabilidad que la enfermedad blanco esté presente o ausente, cuando la técnica así lo determinaba. El empleo de una PDR, por su simpleza y buen desempeño (con resultados disponibles el mismo día) produciría una optimización de recursos, podría realizarse en lugares donde el acceso al diagnóstico es limitado y donde su incorporación no requeriría de una infraestructura importante. Por otro lado, en nuestro caso, podría ser utilizada como segunda prueba, para incrementar la especificidad del diagnóstico serológico de la infección por T. cruzi.
Abstract A quick and safe diagnosis of Trypanosoma cruzi infection allows the immediate etiological treatment in clinically manifested cases. In the present work, the performance of the rapid Chagas Ab Rapid SD Bioline (PDR) test for serological diagnosis was evaluated in 100 sera from patients with a presumptive diagnosis of T. cruzi infection, it was compared with the diagnostic standard (serological pair) and this technique was valued to be used within the laboratory routine. The PDR revealed a very good concordance index with respect to the diagnostic standard (Kappa=0.989 [95% CI 0.965-1.000]) and the parameters of sensitivity, specificity, positive and negative predictive values revealed good performance. The Youden index reported good performance of the diagnostic test (J = 0.98 [95% CI 0.93-1.02]); and in the same sense, both the positive likelihood ratio (RV (+) = infinity), and the negative (RV (-) = 0.02 [95% CI 0.00-0.16]) showed an increased probability whether the target disease was present or absent, when the technique so determined. The use of a PDR, due to its simplicity and good performance (with results available on the same day) would produce an optimization of resources, could be carried out in places where access to the diagnosis is limited and where its incorporation would not require an important infrastructure. On the other hand, in our case, it could be used as a second test, to increase the specificity of the serological diagnosis of T. cruzi infection.
Resumo Um diagnóstico rápido e seguro da infecção pelo Trypanosoma cruzi permite a administração imediata de um tratamento etiológico específico nos casos clinicamente manifestos. No presente trabalho, o desempenho do teste rápido Chagas Ab Rapid SD Bioline (PDR) para o diagnóstico sorológico foi avaliado em 100 soros de pacientes com diagnóstico provável de infecção por T. cruzi, foi comparado com o padrão diagnóstico (par sorológico) e essa técnica foi avaliada para ser utilizada na rotina do laboratório. O PDR revelou um índice de concordância muito bom em relação ao padrão diagnóstico (Kappa=0,989 [IC 95% 0,965-1.000]) e os parâmetros de sensibilidade, especificidade, valores preditivos positivos e negativos revelaram bom desempenho. O índice de Youden informou um bom desempenho do teste diagnóstico (J = 0,98 [IC 95% 0,93-1,02]); e, no mesmo sentido, tanto a razão de verossimilhança positiva (RV (+) = infinito), quanto a negativa (RV (-) = 0,02 [IC 95% 0,00-0,16]), mostraram uma probabilidade aumentada de a doença-alvo estar presente ou ausente, quando a técnica assim o determinar. A utilização de um PDR, pela sua simplicidade e por um bom desempenho (com resultados disponíveis no mesmo dia) produziria uma otimização de recursos, podendo ser realizado em locais onde o acesso ao diagnóstico é limitado, e onde a sua incorporação não exigiria um infraestrutura importante. Por outro lado, no nosso caso, poderia ser utilizado como segundo teste, para aumentar a especificidade do diagnóstico sorológico da infecção pelo T. cruzi.
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Humanos , Trypanosoma cruzi/crescimento & desenvolvimento , Cromatografia de Afinidade , HIV , Parasitologia , Rutina , Doença , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Doença de Chagas , Técnicas de Laboratório Clínico , Técnicas e Procedimentos Diagnósticos , Testes Diagnósticos de Rotina , Eficiência , Recursos em Saúde , Infecções , Laboratórios , MétodosRESUMO
Resumen La criptococosis meníngea presenta alta mortalidad mundial, especialmente en población VIH/sida. La OMS recomienda detectar el antígeno capsular de Crypto coccus como estrategia para un diagnóstico temprano y poder minimizar complicaciones. Objetivo: realizar antigenemia temprana de Cryptococcus mediante in munocromatografía/ensayo de flujo lateral en pacientes asintomáticos VIH+. Material y método: estudio descriptivo observacional; entre julio-2016 y mayo-2019 se procesaron mediante ensayo de flujo lateral, muestras de suero de 169 pacientes asintomáticos VIH+, con CD4 ≤120 cel/μL en Barranquilla, Colombia. Ante resultado positivo, se indicó profilaxis con fluconazol; se hizo seguimiento a todos los casos. Resultados: la antigenemia fue positiva en cinco pacientes (2,96%); uno falleció, cuatro recibieron profilaxis y la prueba se negativizó en dos. Los pacientes con resultado negativo inicial no desarrollaron durante el estudio sinto matología compatible con esta micosis. Discusión: el ensayo de flujo lateral de Cryptococcus está recomendado para el diagnóstico temprano de la criptococosis en población VIH/sida. Conclusión: detectar tempranamente el antígeno circulante de Cryptococcus mediante ensayo de flujo lateral en pacientes asintomáticos VIH+, permitió instaurar profilaxis oportuna, hacer seguimiento y control para reducir la mortalidad asociada con la criptococosis meníngea.
Abstract Meningeal cryptococcosis presents high levels of global mortality, especially in the HIV/AIDS population. The WHO recommends detecting the capsular antigen as an important strategy for early diagnosis and be able to minimize complications. Objective: Perform early cryptococcal antigenemia by immunochromatographic/ lateral flow assay in asymptomatic HIV+ patients. Material and method: descriptive observational study; between July-2016 and May-2019, serum samples from 169 asymptomatic HIV+ patients with CD4 ≤120 cells/μL were processed by lateral flow assay in Barranquilla, Colombia. Given a positive result, prophylaxis with fluconazole was indicated; all cases were followed up. Results: antigenemia was positive in five (2.96%) patients; one died; four received prophylaxis, and the test turned negative in two. The patients with an initial negative result, did not developed symptoms compatible with this mycosis during the study period. Discussion: lateral flow assay for Cryptococcus is recommended for the early diagnosis of cryptococcosis in the HIV/AIDS population. Conclusion: early detection of circulating Cryptococcus antigen by lateral flow assay in HIV+ patients allowed the establishment of timely prophylaxis, follow-up, and control to reduce mortality associated with meningeal cryptococcosis.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Síndrome da Imunodeficiência Adquirida , Criptococose , Antígenos CD4 , HIV , Assistência ao Convalescente , Cryptococcus , MeningiteRESUMO
RESUMEN Introducción: La infección por Helicobacter pylori es cada vez más frecuente en los jóvenes peruanos e incrementa su riesgo de padecer neoplasias gástricas. Objetivo: Determinar los hábitos alimentarios y de higiene asociados a la seroprevalencia de infección por Helicobacter pylori en estudiantes universitarios del departamento de Cajamarca, Perú, durante los meses de septiembre a octubre de 2019. Método: Estudio observacional, transversal, prospectivo con un diseño no experimental. La población estuvo conformada por 367 estudiantes de la carrera profesional de Tecnología Médica. El tamaño de la muestra fue de 188 estudiantes de ambos géneros. Se detectaron anticuerpos IgG frente a Helicobacter pylori en suero, mediante el método de inmunocromatografía. Los hábitos alimentarios y de higiene se recopilaron utilizando una encuesta estructurada. Resultados: El 51,1 % de estudiantes presentó anticuerpos IgG frente a Helicobacter pylori. El 31,38 % de los estudiantes que consumía "a veces" alimentos elaborados en la calle resultaron seropositivos a Helicobacter pylori. Aquellos estudiantes que manifestaron lavarse las manos "a veces" (29,79 %) y "siempre" (21,28 %) antes de ingerir los alimentos presentaron anticuerpos IgG contra la bacteria. Además, los estudiantes seropositivos frente a Helicobacter pylori lavaban sus frutas y verduras con el agua del grifo (43,62 %) y consumían agua de grifo no tratada (29,79 %). Conclusión: El consumo de alimentos preparados en la calle, lavado de manos antes de consumir alimentos, tipo de agua para consumo y lavado de frutas y verduras antes de ingerirlas son hábitos alimentarios y de higiene asociados a la seroprevalencia de Helicobacter pylori.
ABSTRACT Introduction: Helicobacter pylori infection is becoming more frequent in the young population of Peru and at the same time increases the risk of gastric neoplasms. Objective: To identify the dietary and higiene habits associated with the seroprevalence of Helicobacter pylori infection in university students at the Cajamarca Department. Assesed period from September throughout October 2019. Method: An observational, cross-sectional, prospective study with a non-experimental design was carried out. A population of 367 students on Medical technology career were involved and 188 of them, in both sex, were selected as trial. It was detected, using the immunochromatography method in serum assay, IgG antibodies against Helicobacter pylori. Dietary and hygiene habits were collected using a well-structed enquiry. Results: It was identified IgG antibodies against Helicobacter pylori infection in 51.1% of students. The 31.38% of those who, not frequently, had consumed food prepared outdoors were seropositive for Helicobacter pylori. Those students who revealed wash their hands, not frequently (29.79%) and frequently (21.28%) before eating, produced antibodies against this bacterial infection. In addition, Helicobacter pylori seropositive students washed their fruits and vegetables with obtained water from the tap (43.62%) and consumed untreated water fom the tap too (29.79%). Conclusions: Food intake outdoors, wash of hands, fruits and vegetables before eating, and the quality of water to be consumption are dietary and hygiene habits associated with the Helicobacter pylori seroprevalence.
RESUMO Introdução: A infecção por Helicobacter pylori é cada vez mais comum em jovens peruanos e aumenta o risco de neoplasias gástricas. Objetivo: Determinar os hábitos alimentares e de higiene associados à soroprevalência da infecção por Helicobacter pylori em universitários do departamento de Cajamarca, Peru, durante os meses de setembro a outubro de 2019. Método: Estudo observacional, transversal, prospectivo com um não experimental. A população foi composta por 367 alunos da carreira de Tecnologia Médica. O tamanho da amostra foi de 188 alunos de ambos os sexos. Os anticorpos IgG contra Helicobacter pylori foram detectados no soro pelo método de imunocromatografia. Os hábitos alimentares e de higiene foram coletados por meio de questionário estruturado. Resultados: 51,1% dos alunos apresentaram anticorpos IgG contra Helicobacter pylori. 31,38% dos alunos que comeram "às vezes" alimentos preparados na rua eram soropositivos para Helicobacter pylori. Os alunos que relataram lavar as mãos "às vezes" (29,79%) e "sempre" (21,28%) antes de comer apresentaram anticorpos IgG contra a bactéria. Além disso, os alunos soropositivos para Helicobacter pylori lavavam frutas e vegetais com água da torneira (43,62%) e consumiam água da torneira não tratada (29,79%). Conclusão: O consumo de alimentos preparados na rua, a lavagem das mãos antes de consumir os alimentos, o tipo de água para consumo e a lavagem de frutas e verduras antes de ingeri-los são hábitos alimentares e de higiene associados à soroprevalência do Helicobacter pylori.
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Humanos , Higiene dos Alimentos , Helicobacter pylori/isolamento & purificação , Comportamento Alimentar , Peru , Estudantes , Estudos Transversais , Estudos Prospectivos , Tecnologia Biomédica/educação , Estudo ObservacionalRESUMO
Resumen Objetivo: Detectar la presencia de Enterobacterias productoras de carbapenemasas en hisopados rectales de neonatos mediante técnica de nefelometría láser y caracterización del tipo de carbapenemasa mediante test inmunocromatográfico. Materiales y Métodos: Estudio descriptivo de corte transversal. Fueron incluidos 57 neonatos, tamizados al ingreso a UCI, mediante hisopado rectal, procesado por nefelometría laser HB&L Carbapenemase (Alifax®) y caracterización del tipo de carbapenemasa por inmunocromatografía rápida RESIST-3 (Coris BioConcept®). Resultados: Encontramos un alto porcentaje de colonización rectal (22.9%) correspondiente a 13 hisopados positivos y 44 (77.1%) fueron negativos por nefelometría láser. Por VITEK 2® se obtuvo identificación de Klebsiella pneumoniae resistente a carbapenémicos en los 13 aislamientos y el test inmunocromatográfico reveló la presencia de carbapenemasas blaKPC en estos aislamientos. Discusión: Estudios evidencian el aumento de la colonización por microorganismos productores de carbapenemasas en neonatos. Los resultados de este estudio demuestran que un porcentaje significativo de neonatos que ingresan a las Unidades de Cuidado Neonatal se encuentran colonizados con Enterobacterias productoras de carbapenemasas en tracto intestinal. Lo anterior constituye un riesgo potencial para su diseminación y posterior desarrollo de brotes, en donde surge la importancia de implementar estrategias de vigilancia activa como la tamización rectal para la detección oportuna de neonatos colonizados.
Abstract Objective: To detect the presence of carbapenemase-producing Enterobacteriaceae in rectal swabs of neonates by means of laser nephelometry technique and characterization of the type of carbapenemase by immunochromatographic test. Materials and Methods: Descriptive cross-sectional study. 57 neonatal patients were included; They underwent rectal screening upon admission to the ICU, using swabs which were processed by HB&L Carbapenemase laser nephelometry (Alifax®) and characterization of the type of carbapenemase by RESIST-3 rapid immu nochromatography (Coris BioConcept®). Results: We found a high percentage of rectal colonization (22.9%) corresponding to 13 positive swabs and 44 samples (77.1%) were negative by laser nephelome try. Identification of carbapenem-resistant Klebsiella pneumoniae was obtained by VITEK 2® in the 13 isolates and the immunochromatographic test revealed the presence of blaKPC carbapenemases in these isolates. Discussion: Studies show increased colonization by carbapenemase-producing microorganisms in neonates. The results of this study demonstrate that a significant percentage of neonates who enter Neonatal Care Units are colonized with Enterobacteriaceae that produce carbapenemases in the intestinal tract. This constitu tes a potential risk for its spread and subsequent development of outbreaks, where the importance of implementing active surveillance strategies such as rectal screening for the timely detection of colonized neonates arises.
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Carbapenêmicos , Técnicas e Procedimentos Diagnósticos , Enterobacteriaceae , Programas de Rastreamento , Estudos Transversais , Conduta Expectante , Unidades de Terapia Intensiva , Nefelometria e TurbidimetriaRESUMO
INTRODUCTION: In order to deal with the current pandemic caused by the novel SARS-CoV-2 coronavirus several serological immunoassays have been recently developed with the objective of being used as a complementary diagnostic tool and to support the RT-PCR technique currently considered the "gold-standard" method. However, these new assays need to be evaluated and validated. The purpose of this study was to assess the performance of five immunoassays (two ELISA and three CLIA assays) and one rapid immunochromatographic test for the detection of anti-SARS-CoV-2 antibodies. METHODS: Five semiquantitative immunoassays (MENARINI®, PALEX®, VIRCLIA®, ROCHE® and SIEMENS®) and one lateral flow rapid test (WONDFO®) were performed. A total of 124 samples were studied. Case serum samples (n=78) were obtained from COVID-19 patients confirmed by real-time RT-PCR/epidemiological-clinical-radiological criteria, and control non-SARS-CoV-2 samples (n=46) belonged to healthy healthcare workers involved in a seroprevalence study. RESULTS: Overall, the tests showed sensitivities around 70-90% and specificities greater than 95%, including the immunochromatographic test. In addition, we observed very good agreements among them, being better for the detection of IgG than for IgM antibodies (Cohen's kappa index of 0.95 for VIRCLIA® IgG with ROCHE®), as well as good diagnostic power of the tests as determined by the ROC curves. CONCLUSIONS: This study demonstrates the proper performance of the different immunoassays in order to be applied in the clinical practice as support in the diagnostic approach and in the development of vaccines and seroepidemiological studies of COVID-19.
RESUMO
RESUMEN La Organización Mundial de la Salud (OMS) define salmonelosis como una de las enfermedades transmitida por alimentos (ETA) de mayor casuística, ampliamente extendida en todo el mundo. La enfermedad es producida por Salmonella spp. y causa una de las zoonosis más frecuentes y de mayor impacto económico. El hombre adquiere la infección después de la ingestión de alimentos contaminados, aunque también puede transmitirse de persona a persona o por vía fecal-oral. Actualmente, las técnicas micro-biológicas de aislamiento convencional para detección de Salmonella spp. son establecidas por el Código Alimentario Argentino para verificar la aptitud de un producto para consumo, pero éstas requieren de 4 a 5 días para la obtención de un resultado, tiempo que juega en contra para el productor y la conservación de dichos alimentos. Por este motivo en este trabajo se analizan los métodos de diagnóstico tradicional según Normas ISO 6579:2002 con algunas modificaciones, los métodos de inmunoensayo comerciales y la Reacción en Cadena de la Polimerasa técnica (PCR) de detección del gen invA implicado en el proceso de invasión de cepas patógenas. Se analizaron 60 muestras procedentes de canales porcinas destinadas a comercialización. Se detectó un 10% de Salmonella spp. Se pudo determinar que el diagnóstico molecular por PCR posee alta sensibilidad, pero no es alentador el resultado que reflejan los test comerciales inmunocromatográficos ya que queda en evidencia la necesidad de alta carga microbiana para un diagnóstico certero.
ABSTRACT The World Health Organization (WHO) defines salmonellosis as one of the most important foodborne diseases, widely spread worldwide. The disease is produced by Salmonella spp. and causes one of the most frequent zoonoses and of greater economic impact. The infection is acquired after ingestion of contaminated food, although it can also be transmitted from person to person or by fecal-oral route. Currently, conventional isolation microbiological techniques for detection of Salmonella spp. are established by the Argentine Food Code to verify the suitability of a product for consumption. But microbiological techniques require 4 to 5 days to obtain a result, time that plays against the producer and the conservation of such foods. For this reason in this work we analyze the traditional diagnostic methods according to ISO standards 6579: 2002 with some modifications, the commercial immunoassay methods and the Polymerase Chain Reaction technique (PCR) detection of the invA gene involved in the process of invasion of pathogenic strains. Sixty samples from pigs destined for commercialization were analyzed. 10% of Salmonella spp. was detected. It was possible to determine that the molecular diagnosis by PCR has high sensitivity, but it is not encouraging the result that reflect the commercial immunochromatographic tests since it is evident the need of high microbial load for a correct diagnosis.
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El diagnóstico presuntivo de la equinococosis quística (EQ) se basa en estudios clínicos e imagenológicos, en particular aquellos que aplican ultrasonido, en datos epidemiológicos, y se confirma con la serología específica. En las zonas endémicas rurales, donde los procedimientos imagenológicos no siempre se encuentran disponibles, al igual que la serología convencional debido a la falta de laboratorios suficientemente equipados, las pruebas de diagnóstico rápido (TDRs) pueden ser una herramienta de gran utilidad. Se evaluó aquí la precisión diagnóstica de VIRAPID® Hidatidosis (Vircell, España), comparado con dos métodos comerciales usados frecuentemente en este laboratorio, para el diagnóstico de la Hidatidosis: HIDATEST (Laboratorio Lemos, Argentina) y ELISA IgG Echinococcus (Vircell, España). El análisis se realizó sobre 224 muestras de igual número de pacientes; 48 (21,4%) pertenecían a pacientes con quistes probablemente hidatídicos, mientras que 10 (4,5%) a pacientes con quistes no parasitarios. Se agregaron a ellos, 166 (74,1%) muestras que resultaron previamente negativas en la casuística de este laboratorio. Para los tres métodos antes mencionados, la concordancia entre los resultados obtenidos fue evaluada por el estadístico Kappa, donde en todos los casos pudo apreciarse un grado de acuerdo casi excelente. La sensibilidad y especificidad de VIRAPID fueron de 94,1%, 98,9%, ELISA 90,6%, 99,4% e HIDATEST 96,0%, 96,2%, respectivamente. Los TDRs para hidatidosis pueden ser útiles en aquellos entornos con escasos recursos para establecer la certeza diagnóstica. La prueba VIRAPID® Hidatidosis demostró tener un muy buen rendimiento, aunque sería interesante evaluar la sensibilidad del test en presencia de quistes inactivos, lo cual, se supone podría plantear problemas para el diagnóstico.
The presumptive diagnosis of cystic echinococcosis (EQ) is based on clinical and imaging studies, particularly those that apply Ultrasound, in epidemiological data, and is confirmed with specific serology. In rural endemic areas, where imaging procedures are not always available, as with conventional serology due to the lack of sufficiently equipped laboratories, rapid diagnostic tests (TDRs) can be a very useful tool. The diagnostic accuracy of VIRAPID® Hydatidosis (Vircell, Spain) was evaluated here, compared with two commercial methods frequently used in the Laboratory, for the diagnosis of Hydatidosis: HIDATEST (Laboratorio Lemos, Argentina) and ELISA IgG Echinococcus (Vircell, Spain). The analysis was performed on 224 samples from the same number of patients; 48 (21.44%) belonged to patients with probable hydatid cysts, while 10 (4.46%) belonged to patients with non-parasitic cysts. A total of 166 (74.10%) samples that were previously negative in the casuistry of our Laboratory were added. For the three methods mentioned above, the agreement between the results obtained was evaluated by the Kappa statistics, where in all the cases an almost excellent degree of agreement could be appreciated. The Sensitivity and Specificity of VIRAPID® was 94.12%, 98.88%, ELISA 90.57%, 99.44% and HIDATEST 96.00%, 96.17%, respectively. TDRs for hydatidosis may be useful in settings with limited resources to establish diagnostic certainty. The VIRAPID® test showed a very good performance, although it would be interesting to evaluate the sensitivity of the test in the presence of inactive cysts, which can pose problems for the diagnosis.
O diagnóstico presuntivo de equinococose cística (EQ) baseia em estudos clínicos e de imagem, em particular aqueles que aplicam ultrasom, em dados epidemiológicos, e é confirmado com a sorologia específica. Em áreas endêmicas rurais, onde os procedimentos de imagens nem sempre estão disponíveis, como acontece com a sorologia convencional devido à falta de laboratórios suficientemente equipamentados, os testes de diagnóstico rápido (TDRs) podem ser uma ferramenta de grande utilidade. A precisão do diagnóstico de VIRapid® hidatidose (Vircell, Espanha) foi avaliada aqui, em comparação com dois métodos comerciais frequentemente usados neste laboratório, para o diagnóstico de Hidatidose: HIDATEST (Laboratório Lemos, Argentina) e ELISA IgG Echinococcus (Vircell, Espanha). A análise foi realizada em 224 amostras do mesmo número de pacientes; 48 (21,4%) pertenciam a pacientes com cistos provavelmente hidatídicos, enquanto 10 (4,5%) pertenciam a pacientes com cistos não parasitários. Adicionaram-se a eles 166 (74,1%) amostras que resultaram previamente negativas na casuística desse Laboratório. Para os três métodos citados acima, a concordância entre os resultados obtidos foi avaliada pela estatística Kappa, onde em todos os casos um grau de concordância quase excelente pôde ser apreciado. Sensibilidade e especificidade de VIRapid® foi de 94,1%, 98,9%, ELISA 90,6%, 99,4% e HIDATEST, 96,0% e 92,6%, respectivamente. Os TDRs para hidatidose podem ser úteis em ambientes com recursos limitados para estabelecer a certeza diagnóstica. O teste VIRAPID® Hidatidose mostrou ter desempenho muito bom, apesar de que seria interessante avaliar a sensibilidade do teste em presença de cistos inativos, o que se supõe pode causar problemas para o diagnóstico.
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Equinococose , Equinococose/diagnóstico , Métodos , Sorologia , Ultrassom , Cromatografia de Afinidade , Cistos , Casuísmo , Testes Diagnósticos de Rotina , Echinococcus , Eficiência , Recursos em SaúdeRESUMO
El presente es un estudio de tipo descriptivo no experimental para determinar sangre oculta de heces (SOH) en población aparentemente sana. La presencia de SOH, puede estar relacionada con varias causas, como gastritis, úlcera péptica o duodenal, parasitosis intestinal, sangrado de encías o cáncer colorectal. Se analizaron 1093 muestras de heces fecales provenientes de estudiantes que cursaban la cátedra de Anatomía y Fisiología de la FCFB de la UMSA y su entorno familiar. Utilizando el método inmunocromatográfico (SUMASOHF), todos los investigadores que participaron fueron capacitados para realizar el análisis. Las muestras se procesaron, por duplicado y aquellas que dieron resultado positivo, se procesaron nuevamente. Los resultados se analizaron con el programa estadístico SPSS 22. Se encontró presencia de SOH en el 16,1% de todas las muestras procesadas. El porcentaje de casos positivos de SOH fue ligeramente superior en el género masculino y en el grupo etario de 61-80 años. En el grupo de fumadores se reveló un 24.50% de casos positivos y un 19.20% en las personas que declararon consumir bebidas alcohólicas. También se consideraron otras causas de SOH, como la insuficiencia cardiaca, la gastritis, la ingestión de medicamentos como la aspirina y el ibuprofeno. A todos los casos que dieron positivo de SOH, se recomendó consultar con su médico para realizar otros exámenes más específicos. En conclusión la pérdida de sangre por heces fecales es un problema, que puede pasar desapercibido por la ausencia de sintomatología; por lo tanto, sugerimos que esta prueba sea incluida en la evaluación rutinaria de pacientes.
A descriptive, non-experimental study was carried out to determine the presence of fecal occult blood (SOH) considering its relation with the early diagnosis of colorectal cancer. We analyzed 1093 fecal samples from students who were in the Chair of Anatomy and Physiology of the FCFB of UMSA and their family environment. Using the immunochromatographic method (SUMASOHF), all the researchers who participated were trained to perform the analysis. The samples were processed in the laboratory of Anatomy and Physiology, using a inmunocromatographic metod, (SUMASOHF). The investigatours were trained to perform the test and the samples were processed with the supervision of the professors. All samples were processed in duplicate and all positive samples were reprocessed. All results were registrated in the correspondy datasheet. The data were analysed using the a statistical program SPSS 22. We found presence of fecal occult blood in 16.1 % of the samples. The percentage of positive cases of SOH in the male gender was slightly higher compared to the number of positive cases was higher in goner of 61 to 80 age group. In the group of smokers revealed a 24.50% of positive cases and 19.20% in the group that consumes alcohol. Other causes of SOH were also investigated such as heart failure, gastritis, ingestion of drugs such as aspirin and ibuprofen. In some cases, no probable cause of bleeding was found. It was recommended to all participant with a positive test, consult their doctors for more specific diagnosis. Here were concluded that stool blood loss is a problem, which is ignored since there is absence of symptomatology, therefore, we suggest that this test be included in the routine evaluation of patients.
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Doenças Parasitárias , Sangue Oculto , Pacientes , Úlcera Péptica , Ibuprofeno , Fezes , Fumantes , GastriteRESUMO
RESUMEN Objetivo Evaluar la utilidad de ELISA, PCR e inmunocromatografía para el diagnóstico de chikungunya. Métodos Se realizó un metanálisis de estudios que reportaran datos de validez diagnóstica, a partir de un protocolo ex-ante con seis estrategias de búsqueda en tres bases de datos multidisciplinarias. Se garantizó la reproducibilidad en la selección y extracción de información, se evaluó la calidad con la guía QUADAS (Quality Assessment of studies of Diagnostic Accuracy), los análisis se realizaron en MetaDisc con medidas puntuales, intervalos de confianza y resultados combinados bajo un modelo de efectos aleatorios. Resultados Se incluyeron 19 estudios, uno con ELISA para anticuerpos IgG, dos con ELISA para antígenos, cinco con ELISA de anticuerpos IgM, ocho con qPCR y tres con inmunocromatografía. Los artículos fueron publicados entre 2009 y 2015, principalmente en India (37%), usando como prueba de referencia la combinación de sintomatología clínica, RT-PCR, ELISA, ensayo de neutralización o aislamiento viral. La población fue 1 108 individuos sanos, 394 con otra infección (principalmente dengue) y 1 288 con chikungunya. En ELISA para IgM y qPCR la sensibilidad y especificidad fueron mayores al 90%, el cociente de probabilidad positivo mayor a 10, el cociente de probabilidad negativo menor a 0,1; razón de Odds diagnóstica mayor a 100 y área bajo la curva de 0,99. Conclusión Se halló una excelente utilidad diagnóstica de la ELISA IgM y qPCR, mientras que para inmunocromatografía la utilidad fue escasa.
ABSTRACT Objective Evaluate the usefulness of ELISA, PCR, and immunochromatography for the diagnosis of Chikungunya. Methods A meta-analysis of studies reporting diagnostic validity data was performed, using an ex-ante protocol with six search strategies in three multidisciplinary databases. Replicability in the selection and retrieval of information was guaranteed; quality was evaluated using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) guide; the analyses were performed in MetaDisc, with specific measures, confidence intervals, and combined results under a random-effects model. Results A total of 19 studies were included, one with IgG ELISA, two with antigencapture ELISA, five with IgM ELISA, eight with qPCR, and three with immunochromatography. The articles were published primarily in India (37%) between 2009 and 2015, using a combination of clinical symptoms, RT-PCR, ELISA, neutralization assay, or viral isolation as the reference test. The population consisted of 1 108 healthy individuals, 394 with another infection (mainly dengue), and 1 288 with Chikungunya. In IgM ELISA and qPCR, the sensitivity and specificity were greater than 90%, the positive probability quotient was greater than 10, the negative probability quotient was less than 0.1, the diagnostic odds ratio was greater than 100, and the area under the curve was 0.99. Conclusion IgM ELISA and qPCR were found to be excellent for diagnosis, while immunochromatography was only of limited usefulness.
RESUMO Objetivo Avaliar a utilidade dos exames ELISA, PCR e imunocromatografia no diagnóstico de febre chikungunya. Métodos Uma meta-análise de estudos com dados de validade diagnóstica foi conduzida em três bases de dados multidisciplinares segundo um protocolo de avaliação ex-ante contendo seis estratégias de busca. Foi garantida a reprodutibilidade na seleção e extração de informação e avaliada a qualidade segundo os critérios do guia QUADAS (Quality Assessment of Studies of Diagnostic Accuracy). As análises foram realizadas no programa Meta-DiSc com estimativas pontuais, intervalos de confiança e resultados combinados em um modelo de efeitos aleatórios. Resultados A meta-análise incluiu 19 estudos, a saber: um sobre ELISA de anticorpos IgG, dois sobre ELISA de antígenos, cinco sobre ELISA de anticorpos IgM, oito sobre PCR quantitativa (qPCR) e três sobre imunocromatografia. Os artigos foram publicados entre 2009 e 2015, sobretudo na Índia (37%), e usaram como referência critérios clínicos, PCR em tempo real (RT-PCR), ELISA, ensaio de neutralização ou isolamento viral. A população abrangeu 1.108 indivíduos saudáveis, 394 que apresentavam outra infecção (mais comumente, dengue) e 1.288 com febre chikungunya. Com relação ao ELISA-IgM e qPCR, a sensibilidade e a especificidade foram superiores a 90%, a razão de probabilidade positiva foi maior que 10 e a razão de probabilidade negativa menor que 0,1, a razão de chances diagnóstica foi maior que 100 e a área sob a curva foi de 0,99. Conclusão Verificou-se excelente utilidade diagnóstica do ELISA-IgM e qPCR e baixa utilidade da imunocromatografia no diagnóstico de febre chikungunya.
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Ensaio de Imunoadsorção Enzimática , Vírus Chikungunya/patogenicidade , Reação em Cadeia da Polimerase/métodos , Metanálise como Assunto , Cromatografia de AfinidadeRESUMO
A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access.
Para determinar la prevalencia en la ciudad de Buenos Aires del virus de la inmunodeficiencia felina (FIV) y del virus de la leucemia felina (FeLV), y analizar los factores de riesgo que pudieran estar asociados a ellos, se realizó un estudio transversal en gatos atendidos en el Hospital de Pequeños Animales de la Facultad de Ciencias Veterinarias de la Universidad de Buenos Aires. Se analizaron por serología (inmunocromatografía --#91;IA--#93;) y por hemi-nested PCR (n-PCR) 255 muestras de sangre de gatos con síntomas compatibles con infección por FIV o FeLV. La IA y la n-PCR revelaron porcentajes similares de animales positivos para FIV, mientras que para FeLV el diagnóstico por n-PCR resultó más sensible. Se discuten las diferencias halladas entre los métodos diagnósticos y su elección según la edad del animal. Las historias clínicas de 90 de los 255 gatos mostraron perfiles sanguíneos similares a otros ya reportados y revelaron el mayor riesgo de infección con ambos virus en machos adultos con acceso al exterior.
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Animais , Gatos , Doenças do Gato/sangue , Vírus da Imunodeficiência Felina/crescimento & desenvolvimento , Vírus da Leucemia Felina/crescimento & desenvolvimento , Reação em Cadeia da Polimerase/métodos , Prevalência , Fatores de Risco , Vírus da Imunodeficiência Felina/patogenicidade , Vírus da Leucemia Felina/patogenicidadeRESUMO
A cross-sectional study was carried out on cats attending the Small Animal Hospital at the Faculty of Veterinary Sciences of the University of Buenos Aires to assess the prevalence and associated risk factors of Feline immunodeficiency virus (FIV) and Feline leukemia virus (FeLV) in the city of Buenos Aires, Argentina. Blood samples from 255 cats with symptoms compatible with FIV or FeLV infection, collected between 2009 and 2013 were analyzed by serology (immunochromatography, IA) and by hemi-nested PCR (n-PCR). The IA and n-PCR assays showed similar percentages of positivity for FIV while the n-PCR test was more sensitive for FeLV. Differences between the diagnostic tests and their choice according to the age of the animal are discussed. The clinical histories of ninety of the 255 cats showed blood profiles similar to others previously reported and revealed a higher risk of infection in male adult cats with outdoor access.
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Cromatografia de Afinidade/métodos , Síndrome de Imunodeficiência Adquirida Felina/diagnóstico , Vírus da Imunodeficiência Felina/isolamento & purificação , Vírus da Leucemia Felina/isolamento & purificação , Leucemia Felina/diagnóstico , Reação em Cadeia da Polimerase/métodos , Viremia/diagnóstico , Animais , Argentina/epidemiologia , Gatos/virologia , Estudos Transversais , DNA Viral/análise , Síndrome de Imunodeficiência Adquirida Felina/epidemiologia , Síndrome de Imunodeficiência Adquirida Felina/virologia , Feminino , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/imunologia , Vírus da Leucemia Felina/genética , Vírus da Leucemia Felina/imunologia , Leucemia Felina/epidemiologia , Leucemia Felina/virologia , Masculino , Prevalência , Provírus/isolamento & purificação , Kit de Reagentes para Diagnóstico , Fatores de Risco , Sensibilidade e Especificidade , Viremia/epidemiologia , Viremia/virologiaRESUMO
Introduction: The specific diagnosis of influenza A infection makes it possible to control its spread, decreases the unnecessary use of antibiotics, clinical procedures and laboratory test, and allows early recognition of outbreaks. Different technologies are currently available in Chile for this purpose. Objective: The study presented here compares the sensitivity for influenza A virus detection of immunocromatography (RIDT), direct fluorescent antibodies-DFA and DFA with cytocentrifugation against the gold standard, RT-PCR. Material and Methods: In 175 nasal swab samples influenza A RIDT and RT-PCR were performed. Another 1689 nasal swab samples were tested by DFA and RT-PCR for influenza A. Finally, 29 nasal swab samples confirmed as Influenza A positive by RT-PCR were tested by DFA with cytocentrifugation. Results: The RIDT, DFA and DFA + cytocentrifugation sensitivity was 47,3%, 57,2% and 72,4%, respectively. Discussion and Conclusion: Their lower cost and faster turnaround time when compared to PCR make RIDT and DFA the tests of choice in diagnostic laboratories in Chile. However, their low sensitivity and NPV, especially during low season, makes more sensitive diagnostic tools necessary to confirm the results. In our study cytocentrifugation increased DFA sensitivity from 57% to 72%.
Introducción: El diagnóstico específico de influenza permite controlar la diseminación de la enfermedad, disminuir el uso de antimicrobianos, procedimientos clínicos y exámenes, e identificar rápidamente brotes. Diferentes tecnologías están actualmente disponibles en Chile para este propósito. Objetivo: Comparar la sensibilidad diagnóstica para la infección por el virus influenza A de las técnicas inmunocromatografía, inmunofluorescencia directa-IFD e IFD con citocentrifugado contra el estándar de oro, RPC-TR. Materiales y Método: En 175 muestras de hisopado nasofaríngeo se realizó inmunocromatografía y RPC-TR para influenza A. Otras 1.689 muestras de hisopado nasofaríngeo fueron procesadas mediante IFD y RPC-TR para influenza A. Finalmente, en 29 muestras de hisopado nasofaríngeo, confirmadas positivas para influenza A mediante RPC-TR, se realizó IFD con citocentrifugado. Resultados: La sensibilidad de la inmunocromatografía, IFD e IFD + citocentrifugado fue de 47,3%, 57,2% y 72,4%, respectivamente. Discusión y Conclusión: El menor costo y tiempo de respuesta de las técnicas rápidas (inmunocomatografía e IFD) en relación a la RPC-TR hacen que se mantengan como exámenes de rutina en los laboratorios diagnósticos del país. Sin embargo, su baja sensibilidad y VPN, especialmente durante períodos de baja prevalencia, obligaría a confirmar los resultados negativos con técnicas más sensibles. En nuestra comparación la citocentrifugación mejoró la sensibilidad de la IFD de 57% a 72%.
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Humanos , Influenza Humana/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Técnica Direta de Fluorescência para Anticorpo/métodos , Cromatografia de Afinidade , Sensibilidade e EspecificidadeRESUMO
Due to the lack of a rapid, sensitive and specific test to detect the presence of the porcine influenza virus that offers advantages in field conditions, it is necessary to try different options to obtain a rapid and reliable diagnosis. To do so, samples of nasal mucus, obtained with sterile swabs, were taken from 100 pigs with signs of the presence of such virus. These samples were used to compare two different methods for the detection of the porcine influenza virus. The first one was a commercial test, which is based on a rapid immunochromatography designed to detect the influenza virus type A in poultry. The second method consisted in the viral isolation in cell culture, using MDCK cells sensitized with trypsin; this method, already described in former processes, was compared with the first method, using nasal mucus samples from possible infected pigs with the influenza virus. The results showed that in the immunochromatography test, ten samples were positive, while only eight in the cell culture. Therefore, the immunochromatography was 100% sensitive to detect the influenza virus. The development of this work is important because it offers options in the porcine influenza diagnosis in field conditions, using the rapid immunochromatography test, which suggests that the results must be confirmed in the diagnostic laboratory through viral isolation.
Debido a la falta de una prueba rápida, sensible y específica para detectar la presencia del virus de influenza porcina, que ofrezca la ventaja de utilizar aquélla en condiciones de campo, es necesario probar diferentes opciones para obtener un diagnóstico rápido y confiable. Para ello se utilizaron 100 cerdos con signos de dicho virus; de cada uno de ellos se tomaron muestras de moco nasal obtenidas con hisopos estériles y se compararon dos métodos diferentes para la detección del virus de influenza porcina. El primero de ellos fue una prueba comercial, que está basada en una inmunocromatografía rápida diseñada para detectar virus de influenza tipo A en aves. El segundo método fue el aislamiento viral en cultivo celular en células MDCK sensibilizadas con tripsina; este método, ya descrito en otros trabajos, se comparó con el primer método a partir de muestras de moco nasal de cerdos sospechosos de estar infectados con el virus. Los resultados mostraron que en la prueba de inmunocromatografía, diez muestras fueron positivas y ocho en cultivo celular; la prueba de inmunocromatografía fue 100% sensible para detectar el virus de influenza. El desarrollo de este trabajo es importante, ya que ofrece opciones para el diagnóstico de influenza porcina en campo con el uso de la prueba rápida de inmunocromatografía y sugiere que los resultados deberán confirmarse en el laboratorio de diagnóstico mediante el aislamiento viral.
RESUMO
Con la finalidad de mejorar el diagnóstico de laboratorio de sífilis como enfermedad infecto contagiosa en donantes de sangre, se realizó el presente estudio cuyo objetivo es determinar las pruebas serológicas específicas: Inmunoanálisis Enzimático (ELISA), Inmunocromatografía (IC) e inespecíficas: Laboratorio de investigación de enfermedades venéreas (VDRL) y Reaginas séricas no calentadas (USR) más confiable para el descarte de sífilis en donantes de sangre del Hospital Dr. Adolfo Pons de Maracaibo, estado Zulia. Se analizaron 481 sueros de donantes de sangre aparentemente sanos, de ambos sexos en edades comprendidas entre 18 y 60 años. Del total de muestras analizadas por ELISA 10 resultaron positivas (2,07 por ciento) y 8 (1,66 por ciento) por IC. El VDRL captó 4 (0,82 por ciento) sueros con reactividad y USR sólo 2 sueros (0,41 por ciento). Se concluye que la prueba de ELISA conjuntamente con el VDRL son las herramientas más seguras y fidedignos para el descarte de sífilis en donantes de sangre, dado que proporcionan en paralelo resultados confiables, fidedigno que garantice la calidad de la misma al ser transfundida
In order to improve the laboratory diagnosis of syphilis as an infectious and contagious disease in blood donors, we performed this study to determine the reliability of the specific: Enzyme Immunoassay (Elisa) and Immune-chromatography (IC) tests, the unspecific: Venereal Disease Research Laboratory (VDRL) test and the Unheated serum regain (USR) Serologic tests to rule out syphilis from blood donors of the Dr Adolfo Pons Hospital in Maracaibo, Zulia state. We analyzed 481 sera from apparently healthy blood donors, male and female, 18 to 60 years of ages. From the samples analyzed by Elisa 10 were positive (2.07 percent) and 8 (1.66 percent) by IC. VDRL detected 4 (0.82 percent) reactive sera and USR just 2 (0.421 percent). We concluded that Elisa with VDRL are the safest and more reliable tests to rule out syphilis from blood donors, since they gave in parallel reliable results to assure the quality of blood to be transfused