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OBJECTIVE: to evaluate the quality of the sputum sample before and after the Nursing guidance to patients. METHODS: this is a quasi-experimental research design, single group type, before and after, non-randomized study. The study enrolled patients with suspected pulmonary tuberculosis, respiratory symptomatic patients for over three weeks, aged over 18 years, of both genders and without tuberculosis history in the last two years. The educational intervention consisted of individualized guidance on the collection of sputum sample, which was based on the guidelines of the Ministry of Health of Brazil and on the explanatory folder delivery. RESULTS: in this study participated 138 patients with suspected pulmonary tuberculosis. The results showed significant increase of the samples with purulent particles, volume greater than 5 mL and increased rate of patients diagnosed with tuberculosis, after the educational intervention. CONCLUSION: it was shown that after the educational intervention, it was observed sputum samples with better quality, with satisfactory aspect and volume for the effectiveness of the bacilloscopic examination.
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Manejo de Especímenes , Esputo , Tuberculosis Pulmonar/diagnóstico , Educación en Enfermería , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados no Aleatorios como Asunto , Guías de Práctica Clínica como AsuntoRESUMEN
Abstract Objective: to evaluate the quality of the sputum sample before and after the Nursing guidance to patients. Methods: this is a quasi-experimental research design, single group type, before and after, non-randomized study. The study enrolled patients with suspected pulmonary tuberculosis, respiratory symptomatic patients for over three weeks, aged over 18 years, of both genders and without tuberculosis history in the last two years. The educational intervention consisted of individualized guidance on the collection of sputum sample, which was based on the guidelines of the Ministry of Health of Brazil and on the explanatory folder delivery. Results: in this study participated 138 patients with suspected pulmonary tuberculosis. The results showed significant increase of the samples with purulent particles, volume greater than 5 mL and increased rate of patients diagnosed with tuberculosis, after the educational intervention. Conclusion: it was shown that after the educational intervention, it was observed sputum samples with better quality, with satisfactory aspect and volume for the effectiveness of the bacilloscopic examination.
Resumo Objetivo: avaliar a qualidade da amostra de escarro antes e após as orientações de Enfermagem ao paciente. Métodos: estudo com delineamento de pesquisa quase experimental, do tipo grupo único, antes e depois, não randomizado. Participaram do estudo pacientes com suspeita de tuberculose pulmonar, sintomáticos respiratórios por mais de três semanas, maiores de 18 anos, de ambos os sexos e sem antecedente de tuberculose nos últimos dois anos. A intervenção educativa consistiu em orientações individualizadas sobre a coleta da amostra de escarro, fundamentadas nas diretrizes do Ministério da Saúde do Brasil e na entrega de folder explicativo. Resultados: participaram 138 pacientes com suspeita de tuberculose pulmonar. Os resultados evidenciaram importante acréscimo das amostras com partículas purulentas, volume maior que 5mL e aumento na taxa de pacientes diagnosticados com tuberculose, após a intervenção educativa. Conclusão: comprovou-se que, após a intervenção educativa, obtiveram-se amostras de escarro com maior qualidade, com aspecto e volume satisfatórios para efetividade do exame baciloscópico.
Resumen Objetivo: evaluar la calidad de la muestra de esputo antes y después de las orientaciones de Enfermería al paciente. Métodos: de estudio con diseño de investigación casi experimental, del tipo grupo único, antes y después, no aleatorio. Participaron del estudio pacientes con sospecha de tuberculosis pulmonar, sintomáticos respiratorios por más de 3 semanas, mayores de 18 años, de los dos sexos y sin antecedente de tuberculosis en los últimos dos años. La intervención educativa consistió en orientaciones individualizadas sobre la recolección de la muestra de esputo, fundamentadas en las directrices del Ministerio de la Salud de Brasil y en la entrega de folder explicativo. Resultados: participaron 138 pacientes con sospecha de tuberculosis pulmonar. Los resultados evidenciaron un importante aumento de las muestras con partículas purulentas, volumen mayor que 5mL y aumento en la tasa de pacientes diagnosticados con tuberculosis, después de la intervención educativa. Conclusión: se comprobó que, después de la intervención educativa, se obtuvieron muestras de esputo con mejor calidad, con aspecto y volumen satisfactorios para efectividad del examen de baciloscopía.
Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Manejo de Especímenes , Esputo , Tuberculosis Pulmonar/diagnóstico , Guías de Práctica Clínica como Asunto , Educación en Enfermería , Ensayos Clínicos Controlados no Aleatorios como AsuntoRESUMEN
Antecedentes. Los métodos actuales para el diagnóstico de laboratorio de la histoplasmosis son problemáticos si consideramos los valores de sensibilidad, especificidad y tiempo de ejecución. Objetivos. En este estudio hemos tratado de seleccionar y optimizar los métodos para la detección de Histoplasma capsulatum var. capsulatum mediante la reacción en cadena de la polimerasa (PCR). Métodos. Se evaluaron tres métodos de extracción de ADN y tres métodos de PCR. Se optimizó la concentración de los componentes de esta reacción de PCR y se determinó su co-positividad (sensibilidad) y co-negatividad (especificidad), utilizando muestras de sangre a las que se había añadido H. capsulatum. Resultados. El método de extracción que dio el ADN de más alta calidad utiliza membranas de sílice (DNeasy Blood & Tissue Kit, Qiagen, Hilden, Germany), y el método de PCR con mayor capacidad de detección es el que incluye un gen diana que codifica una proteína de 100 kDa. Nuestra optimización de las condiciones de PCR indicaron que la reacción trabaja en un rango significativo de las concentraciones de componentes y, además, fue capaz de detectar H. capsulatum mejor que las técnicas de cultivo tradicional, con un límite de detección de solo 10 pg de ADN. Conclusiones. En nuestras condiciones experimentales, el método PCR seleccionado en este trabajo (en lugar de PCR anidada) es una herramienta lo suficientemente sensible para el diagnóstico de la histoplasmosis
Background. Current methods for the laboratory diagnosis of histoplasmosis are problematic in terms of their sensitivity, specificity and runtime. Objectives. Thus, in this study, we sought to select and optimize methods for the detection of Histoplasma capsulatum var. capsulatum by polymerase chain reaction (PCR). Methods. Three DNA extraction methods and three PCR methods were evaluated. We optimised the concentration of the components of this PCR reaction and determined its sensitivity and specificity using blood samples to which H. capsulatum had been added. Results. The DNA extraction method that yielded the highest-quality DNA used silica membranes (DNeasy Blood & Tissue Kit, Qiagen, Hilden, Germany), and the amplification method with the best detection capacity used a target gene encoding a 100-kDa protein. Our optimisation of the PCR conditions indicated that the reaction works over a significant range of component concentrations; in addition, it was able to detect H. capsulatum better than traditional culture techniques, with a detection limit of only 10 pg of DNA. Conclusions. In our experimental conditions, the PCR method selected in this work (instead of nested-PCR) is a tool sensitive enough for the diagnosis of histoplasmosis(AU)
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Reacción en Cadena de la Polimerasa/instrumentación , Reacción en Cadena de la Polimerasa/métodos , Histoplasma/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Sensibilidad y Especificidad , Histoplasmosis/diagnóstico , Histoplasmosis/microbiología , ADN/análisis , ADN/aislamiento & purificación , ADN/metabolismo , Reacción en Cadena de la Polimerasa/normas , Reacción en Cadena de la Polimerasa/tendencias , Reacción en Cadena de la Polimerasa , Histoplasma/enzimología , Histoplasma/metabolismo , Histoplasma/patogenicidadRESUMEN
As there are four major molecular types of Cryptococcus neoformans (VNI, VNII, VNIII and VNIV) and four molecular types of Cryptococcus gattii (VGI, VGII, VGIII and VGIV), it is important to identify the specific groups causing cryptococcosis in different geographical regions. Here, we investigated the molecular types of 57 cryptococcal isolates from patients in a tertiary care hospital in the state of Amazonas, Brazil, between 2006 and 2010. The isolates were characterised by PCR fingerprinting using the M13 minisatellite and confirmed by URA5-RFLP analysis, and the presence of specific genes from the mating type locus (MATα and MATa) of these species was analysed by PCR. Most of the patients were male (66.7%), between 16 and 30 years of age (51.7%), and HIV-positive (75.0%). Most isolates were collected from cerebrospinal fluid samples (71.7%). Most of the C. neoformans isolates (n=40) were characterised as members of the VNI molecular group (n=39), a unique isolate was characterised as VNII whereas all isolates of C. gattii (n=17) were members of the VGII molecular group. With regard to mating types, 55 isolates were type 'α', and only two were type 'a'. This study revealed the prevalence of the VNI molecular group and provides the first reported observation of the VNII molecular group in the northern region of Brazil.
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Criptococosis/microbiología , Cryptococcus/genética , Cryptococcus/aislamiento & purificación , Adolescente , Adulto , Anciano , Instituciones de Atención Ambulatoria , Brasil/epidemiología , Niño , Preescolar , Criptococosis/epidemiología , Cryptococcus/clasificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Técnicas de Tipificación Micológica , Polimorfismo de Longitud del Fragmento de Restricción , Adulto JovenRESUMEN
This paper presents a new method for segmentation of tuberculosis bacillus in conventional sputum smear microscopy. The method comprises three main steps. In the first step, a scalar selection are made for characteristics from the following color spaces: RGB, HSI, YCbCr and Lab. The features used for pixel classification in the segmentation step were the components and subtraction of components of these color spaces. In the second step, a feedforward neural network pixel classifier, using selected characteristics as inputs, is applied to segment pixels that belong to bacilli from the background. In third step geometric characteristics, especially the eccentricity, and a new proposed color characteristic, the color ratio, are used to noise filtering. The best sensitivity achieved in bacilli detection was 91.5%.
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Microscopía/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Humanos , Mycobacterium tuberculosis/clasificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Esputo/microbiologíaRESUMEN
BACKGROUND: Current methods for the laboratory diagnosis of histoplasmosis are problematic in terms of their sensitivity, specificity and runtime. OBJECTIVES: Thus, in this study, we sought to select and optimize methods for the detection of Histoplasma capsulatum var. capsulatum by polymerase chain reaction (PCR). METHODS: Three DNA extraction methods and three PCR methods were evaluated. We optimised the concentration of the components of this PCR reaction and determined its sensitivity and specificity using blood samples to which H. capsulatum had been added. RESULTS: The DNA extraction method that yielded the highest-quality DNA used silica membranes (DNeasy Blood & Tissue Kit, Qiagen, Hilden, Germany), and the amplification method with the best detection capacity used a target gene encoding a 100-kDa protein. Our optimisation of the PCR conditions indicated that the reaction works over a significant range of component concentrations; in addition, it was able to detect H. capsulatum better than traditional culture techniques, with a detection limit of only 10 pg of DNA. CONCLUSIONS: In our experimental conditions, the PCR method selected in this work (instead of nested-PCR) is a tool sensitive enough for the diagnosis of histoplasmosis.
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Histoplasma/genética , Histoplasma/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodosRESUMEN
Substances that inhibit the growth of Mycobacterium tuberculosis could potentially be used as antibiotics. These substances could also be added to test culture media to improve the speed of tuberculosis diagnosis. The aim of this work was to investigate the influence of culture filtrates of endophytic fungi isolated from P. aduncum L. on the growth of M. tuberculosis. To achieve this objective, the following methodology was used: a) endophytic fungi were isolated from the leaves and stems of P. aduncum L.; b) the isolated fungi were submitted to submerged bioprocessing; c) culture filtrates from the bioprocess were assayed to evaluate their effect on the growth of M. tuberculosis. We isolated 315 fungal types, which represented 85 morphologies, from different parts of P. aduncum L. The bioassays were performed on 82 culture filtrates and 6 plant extracts and resulted in the detection of 1 culture filtrate that stimulated the growth of M. tuberculosis and 15 that inhibited microbial growth. None of the phytochemical extracts had an effect on the growth of M. tuberculosis. In conclusion, we observed that the endophytic fungi isolated from P. aduncum L. (Piperaceae) produced extracellular metabolites (present in the culture filtrate) that affect the growth of M. tuberculosis. These compounds have the potential to be used as antimicrobials or in the diagnosis of tuberculosis.
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Endófitos , Extractos Vegetales/farmacología , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis , Piper , Antiinfecciosos , Bioensayo , Medios de CultivoRESUMEN
This article presents a systematic analysis of focus functions in conventional sputum smear microscopy for tuberculosis. This is the first step in the development of automatic microscopy. Nine autofocus functions are analyzed in a set of 1200 images with varying degrees of content density. These functions were evaluated using quantitative procedures. The main accomplishment of this work was to show that an autofocus function based on variance measures produced the best results for tuberculosis images.
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Interpretación de Imagen Asistida por Computador/instrumentación , Interpretación de Imagen Asistida por Computador/métodos , Microscopía/métodos , Esputo/metabolismo , Tuberculosis/diagnóstico , Tuberculosis/metabolismo , Algoritmos , Diseño de Equipo , Reacciones Falso Positivas , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Modelos Estadísticos , Reproducibilidad de los Resultados , Robótica/instrumentación , Robótica/métodos , Esputo/microbiología , Tuberculosis/microbiologíaRESUMEN
Using bacteriological (culture) and molecular (PCR - Restriction Enzyme Analysis, PRA) methods, we investigated the presence of environmental mycobacteria in tap water, antiseptic solutions and surgical gloves, used in carrying out surgical procedures at the Getúlio Vargas University Hospital Surgical Center, in Manaus -Amazonas/Brazil. Samples (105) were collected and analyzed from: tap water (24 - collected from 3 taps in the surgical center); povidone-iodine solution, PVP-I, (8); Chlorhexidine solution (7), that were used to hygienize surgeons' hands; surgical gloves (39); and solutions that were effectively used during the surgical procedure (27). Using bacteriological method 41 mycobacteria were isolated, all from samples of tap water. Using PRA, mycobacterial DNA was detected only in the sample from water that provided over 100 colonies per inoculated culture tubes. The isolated were identified as Mycobacterium celatum pattern II, M. gordonae pattern III, M. gordonae pattern VI, M. intracellulare pattern I, M. lentiflavum pattern III and M. mucogenicum pattern I. The isolating of M. mucogenicum, a species that had already been incriminated for causing post-surgical outbreaks in tap water from the surgical center, indicates that cleaning and monitoring procedures must be carried out in every place of water distribution. This may be necessary to prevent nosological mycobacteriosis outbreaks induced by the use of water in different activities such as handling and hygienizing patients submitted to invasive procedures.
Investigou-se por métodos bacteriológicos (cultivo) e moleculares (PCR - Restriction Enzyme Analysis, PRA), a presença de micobactérias ambientais em águas de torneira, soluções e luvas cirúrgicas, utilizadas nas etapas dos procedimentos cirúrgicos executados no centro cirúrgico do Hospital Universitário Getulio Vargas (HUGV), na cidade de Manaus-Amazonas/Brasil. Foram colhidas e analisadas 105 amostras sendo: 24 de águas (colhidas das 2 torneiras existentes no centro cirúrgico), 8 de solução de Povidine e 7 de solução de Clorhexidina, que servem para a higienização das mãos dos cirurgiões; 39 de luvas cirúrgicas (superfícies internas e externas); e 27 de soluções que foram efetivamente utilizadas durante o ato cirúrgico. Por método bacteriológico obteve-se 41 isolados micobacterianos apenas de águas das torneiras. Pelo PRA obteve-se a detecção de DNA micobacteriano somente na amostra de água que forneceu acima de 100 colônias de micobactérias por tubo semeado. Os isolados foram identificados como sendo Mycobacterium celatum perfil 2, M. gordonae perfil 3, M. gordonae perfil 6, M. intracellulare perfil 1, M. lentiflavum perfil 3 e M. mucogenicum perfil 1. O encontro de M. mucogenicum, espécie já incriminada em surtos pós-cirúrgicos, indica que devem ser efetuados procedimentos de limpeza e monitoramento em todos os pontos de distribuição de águas, visando à prevenção de surtos de micobacterioses nosocomiais induzidos pelo uso das águas nas diferentes atividades de manuseio ou higienização dos pacientes submetidos a procedimentos invasivos.
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OBJECTIVE: To propose a methodology for characterizing proficiency in sputum smear microscopy for acid-fast bacilli (AFB) in the diagnosis of tuberculosis and to determine the number of microscopies necessary to establish this proficiency, as well as the quality of the transcription of results, the causes of the discrepancies in the readings (rater or microscope used), and the criterion for classification of microscopy results that poses the most difficulty in characterizing proficiency. METHODS: Four hundred sputum smear microscopies for the diagnosis of tuberculosis were analyzed through double-blind readings by six professionals who usually read/supervise microscopies performed in public health care facilities. The sample was stratified to obtain, at least, a reliability of 90% in the double-blind readings, an alpha error of 5%, and a precision of 3%. The results were analyzed using observed reliability and the kappa index. RESULTS: Thirteen errors (0.27%) were found in the transcription of results. Reliability increased when the three distinct categories of positive results (AFB+, AFB++, and AFB+++) were grouped or when inconclusive results were excluded from the analysis. The quantification of the bacterial load was the classification criterion that posed the most difficulty in establishing proficiency. Using higher quality microscopes increased reliability. Reliability values stabilized only from the reading of 75 microscopies onward. CONCLUSIONS: Double-blind sputum smear microscopy readings using a panel containing 75 slides (36 negative, 4 inconclusive, and 35 positive) proved to be appropriate for characterizing proficiency in sputum smear microscopy for the diagnosis of tuberculosis when such proficiency is intended to reproduce laboratory routine.
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Manejo de Especímenes/métodos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Técnicas Bacteriológicas , Técnicas de Laboratorio Clínico , Método Doble Ciego , Reacciones Falso Negativas , Reacciones Falso Positivas , Femenino , Humanos , Masculino , Control de Calidad , Reproducibilidad de los Resultados , Tuberculosis Pulmonar/microbiologíaRESUMEN
OBJETIVO: Propor uma metodologia para caracterizar proficiência na pesquisa de bacilos álcool-ácido resistentes (BAAR) em baciloscopias de escarro para diagnóstico da tuberculose, assim como determinar o número necessário de baciloscopias para estabelecer essa proficiência, a qualidade da transcrição dos resultados, as causas das discordâncias nas leituras (leitor e/ou microscópio utilizado) e o critério de classificação de resultados baciloscópicos que causa maior dificuldade na caracterização de proficiência. MÉTODOS: Quatrocentas baciloscopias de escarro para diagnóstico da tuberculose foram analisadas, mediante leituras duplo-cegas, por seis profissionais que usualmente efetuam leitura/supervisão de baciloscopias realizadas na rede básica de saúde. A amostragem foi determinada visando a obter, no mínimo, 90 por cento de concordância nas leituras duplo-cegas, erro alfa de 5 por cento e precisão de 3 por cento. Os resultados foram analisados mediante concordância observada/índice kappa. RESULTADOS: Constataram-se 13 erros de transcrição dos resultados (0,27 por cento). A concordância aumentou quando as três categorias distintas de resultados baciloscópicos positivos (BAAR+, BAAR++ e BAAR+++) foram agrupadas ou foram excluídos da análise os exames com resultados inconclusivos. A quantificação da carga bacilar foi o critério de classificação que causou maior dificuldade para caracterização de proficiência. A qualidade do microscópio utilizado foi importante para o aumento da concordância. A estabilização dos valores de concordância somente foi obtida a partir da leitura de 75 baciloscopias. CONCLUSÕES: O uso de leituras baciloscópicas duplo-cegas utilizando-se painel composto por 75 lâminas (36 negativas, 4 inconclusivas e 35 positivas) mostra-se adequado para caracterizar a proficiência em baciloscopia para diagnóstico da tuberculose quando essa proficiência pretende reproduzir a rotina laboratorial.
OBJECTIVE: To propose a methodology for characterizing proficiency in sputum smear microscopy for acid-fast bacilli (AFB) in the diagnosis of tuberculosis and to determine the number of microscopies necessary to establish this proficiency, as well as the quality of the transcription of results, the causes of the discrepancies in the readings (rater or microscope used), and the criterion for classification of microscopy results that poses the most difficulty in characterizing proficiency. METHODS: Four hundred sputum smear microscopies for the diagnosis of tuberculosis were analyzed through double-blind readings by six professionals who usually read/supervise microscopies performed in public health care facilities. The sample was stratified to obtain, at least, a reliability of 90 percent in the double-blind readings, an alpha error of 5 percent, and a precision of 3 percent. The results were analyzed using observed reliability and the kappa index. RESULTS: Thirteen errors (0.27 percent) were found in the transcription of results. Reliability increased when the three distinct categories of positive results (AFB+, AFB++, and AFB+++) were grouped or when inconclusive results were excluded from the analysis. The quantification of the bacterial load was the classification criterion that posed the most difficulty in establishing proficiency. Using higher quality microscopes increased reliability. Reliability values stabilized only from the reading of 75 microscopies onward. CONCLUSIONS: Double-blind sputum smear microscopy readings using a panel containing 75 slides (36 negative, 4 inconclusive, and 35 positive) proved to be appropriate for characterizing proficiency in sputum smear microscopy for the diagnosis of tuberculosis when such proficiency is intended to reproduce laboratory routine.
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Femenino , Humanos , Masculino , Manejo de Especímenes/métodos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Técnicas Bacteriológicas , Técnicas de Laboratorio Clínico , Método Doble Ciego , Reacciones Falso Negativas , Reacciones Falso Positivas , Control de Calidad , Reproducibilidad de los Resultados , Tuberculosis Pulmonar/microbiologíaRESUMEN
This article presents an automatic identification method of mycobacterium tuberculosis with conventional microscopy images based on Red and Green color channels using global adaptive threshold segmentation. Differing from fluorescence microscopy, in the conventional microscopy the bacilli are not easily distinguished from the background. The key to the bacilli segmentation method employed in this work is the use of Red minus Green (R-G) images from RGB color format. In this image, the bacilli appear as white regions on a dark background. Some artifacts are present in the (R-G) segmented image. To remove them we used morphological, color and size filters. The best sensitivity achieved was about 76.65%. The main contribution of this work was the proposal of the first automatic identification method of tuberculosis bacilli for conventional light microscopy.
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Algoritmos , Inteligencia Artificial , Interpretación de Imagen Asistida por Computador/métodos , Microscopía/métodos , Mycobacterium tuberculosis/citología , Reconocimiento de Normas Patrones Automatizadas/métodos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
INTRODUÇÃO: A tuberculose cutaneoganglionar (TbCG) corresponde a 25,4 por cento dos casos de tuberculose (Tb) extrapulmonar no estado do Amazonas. Os métodos tradicionais, bacteriológicos e histopatológicos envolvem algumas dificuldades diagnósticas, e a reação em cadeia da polimerase (PCR) surge como método alternativo, podendo propiciar resultados específicos e em menor tempo. Nesse sentido, verificou-se a acurácia do protocolo PCR4 de Marchetti et al. no diagnóstico da TbCG comparativamente aos métodos bacteriológicos e histopatológicos. MATERIAIS E MÉTODOS: Realizou-se o nested-PCR com oligonucleotídeos para a IS6110 do complexo do M. tuberculosis em 83 amostras parafinizadas, sendo 52 cutâneas e 31 ganglionares, de pacientes clinicamente suspeitos de TbCG. Todos os casos foram avaliados pelos métodos bacteriológicos e histopatológicos. Foi realizada análise da acurácia entre os resultados obtidos na PCR em relação ao cultivo e à histopatologia. RESULTADOS E DISCUSSÃO: A positividade da PCR em todos os casos estudados foi de 50,6 por cento (42/83), sendo de 59,6 por cento (31/52) em amostras cutâneas e de 35,5 por cento (11/31) nas ganglionares. Em ambos os grupos foram observados resultados falso-positivos e falso-negativos. Algumas hipóteses que podem justificar estes resultados estão relacionadas à presença da IS6110 em micobactérias ambientais da região amazônica e à não-padronização da amostra de DNA amplificado. CONCLUSÃO: O protocolo em avaliação apresentou positividade em percentual semelhante a diferentes protocolos existentes na literatura. Sugere-se o uso da PCR em tecidos parafinizados associada com o cultivo ou com a histopatologia para o diagnóstico definitivo de Tb ganglionar. Para as lesões cutâneas continua sendo necessária a busca de protocolo que amplie a acurácia do método.
BACKGROUND: Cutaneous lymph node tuberculosis (CLTb) represents 25.4 percent of all cases of extra-pulmonary Tb in the state of Amazonas. The current methods of diagnose including bacteriological and histopathological assays involve some technical difficulties, and the polymerase chain reaction - PCR arise as an alternative method allowing specific results faster than the others. In this context the accuracy of PCR4 Marchetti et al. protocol was compared with traditional methods. MATERIAL AND METHOD: Nested-PCR for IS6110 (123 pb) were applied on 83 CLTb suspicious formalin fixed and paraffin embedded samples of tissues (52 cutaneous and 31 lymph node), obtained from 1997 to 2002. All cases were evaluated by bacteriological and histopathological methods. Accuracy analyses were carried out between the PCR amplification results and those related on bacteriological and histopathological methods. RESULTS AND DISCUSSIONS: Positive results of PCR4 were about 50.6 percent (59.6 percent in cutaneous samples and of 35.5 percent in lymph nodes samples). In both groups were observed false-negative and false-positive results. Some hypotheses that explain those results are related to the presence of IS6110 in environmental mycobacterias in the Amazon region and the absence of standardized DNA concentration to amplification assays. CONCLUSIONS: The proposed protocol was as positive as others ones available in the literature. Definitive Tb diagnostic can be obtained on lymph node paraffin embedded PCR in association with bacteriological or histopathological method. A better accuracy of an amplification assay applied to cutaneous Tb suspicious lesions has to be still under research.
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Humanos , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Tuberculosis Cutánea/diagnóstico , Tuberculosis Ganglionar/diagnóstico , Adhesión en Parafina/métodosRESUMEN
We elaborated an alternative culture method, which we denominated PKO (initials in tribute of respect to Petroff, Kudoh and Ogawa), for isolating Mycobacterium tuberculosis from sputum for diagnosis of pulmonary tuberculosis (TB), and to compare its performance with the Swab and Petroff methods. For the technique validation, sputum samples from patients suspected of pulmonary TB cases were examined by acid-fast microscopy (direct and concentrated smear), PKO, Swab and Petroff methods. We found that Petroff and PKO methods have parity in the effectiveness of M. tuberculosis isolation. However, by the PKO method, 65 percent of isolated strains were detected in a period of £15 days, while by the Petroff method the best detection was in an interval of 16-29 days (71 percent). In positive smear samples, the average time of PKO isolation is only superior to the one related for Bactec 460TB. In conclusion, the exclusion of the neutralization stage of pH in the PKO reduces the manipulation of the samples, diminishes the execution time of the culture according to the Petroff method and facilitates the qualification of professionals involved in the laboratorial diagnosis of Tuberculosis.
Foi elaborado um método de cultivo alternativo, denominado por nós PKO (iniciais referentes à Petroff, Kudoh e Ogawa), para o isolamento do Mycobacterium tuberculosis em amostras de escarro para o diagnóstico da tuberculose pulmonar (TB). Para validação da técnica, amostras de escarro de pacientes suspeitos de TB foram submetidas aos métodos de baciloscopia (direta e pós-concentração), PKO, Swab e Petroff. A análise comparativa entre o método de Petroff e o PKO mostrou paridade de resultados em relação ao isolamento e número de colônias de M. tuberculosis. Porém, pelo método PKO, 65 por cento das cepas isoladas foi detectada em um período £15 dias, enquanto que pelo método de Petroff a melhor detecção ocorreu em um intervalo de 16-29 dias (71 por cento). O tempo médio de isolamento pelo PKO é somente superior ao sistema comercial Bactec 460TB em amostras positivas na baciloscopia. A exclusão da etapa de neutralização de pH no método PKO reduz a manipulação das amostras, diminui o tempo de execução do cultivo em relação ao de Petroff e facilita o treinamento de profissionais que realizam o diagnóstico laboratorial da TB.
Asunto(s)
Tuberculosis , Equipo para Diagnóstico , Mycobacterium tuberculosisRESUMEN
OBJETIVO: Avaliar a acurácia dos métodos bacteriológicos e da reação em cadeia da polimerase com oligonucleotídeos específicos para a IS6110 do complexo Mycobacterium tuberculosis, em amostras de escarro de indígenas e não indígenas. MÉTODOS: Analisaram-se 214 amostras de escarro (154 de indígenas e 60 de não indígenas) quanto à acurácia da baciloscopia direta e pós-concentração, cultivo e reação em cadeia da polimerase. RESULTADOS: Ambos os métodos baciloscópicos, quando comparados com o cultivo ou a reação em cadeia da polimerase foram de baixa sensibilidade. A especificidade variou de 91 por cento a 100 por cento, sendo a baciloscopia pós-concentração menos específica. Nas amostras indígenas constataram-se três vezes mais isolamentos de micobactérias não tuberculosas do que nas não indígenas. Resultados da reação em cadeia da polimerase aparentemente falsos-positivos e negativos foram encontrados com maior freqüência na população indígena. CONCLUSÃO: Baciloscopias positivas para bacilos álcool-acidorresistentes com isolamento de micobactérias não tuberculosas e reação em cadeia da polimerase positiva estabelecem as hipóteses de: existência na Amazônia de espécies de micobactérias não tuberculosas com regiões do DNA homólogas à IS6110 ou ainda que possuam a IS6110, até então só descrita no complexo M. tuberculosis; impossibilidade de isolamento do M. tuberculosis pelo crescimento mais rápido de micobactérias não tuberculosas presentes nas amostras de escarro, por colonização da orofaringe ou da lesão tuberculosa; presença de DNA de M. tuberculosis devida a antecedente de tuberculose. A ausência de positividade em resultados bacteriológicos com reação em cadeia da polimerase positiva sugere questões técnicas inerentes aos métodos bacteriológicos ou precedentes de tuberculose.
OBJECTIVE: To evaluate the accuracy of bacteriological methods and of polymerase chain reaction (with primers specific for IS6110 of the Mycobacterium tuberculosis complex) in testing sputum samples from indigenous (Amerindian) and non-indigenous patients. METHODS: A total of 214 sputum samples (154 from indigenous patients and 60 from non-indigenous patients) were analyzed in order to determine the accuracy of smear microscopy (direct and concentrated versions) for acid-fast bacilli, culture, and polymerase chain reaction. RESULTS: Both microscopy methods presented low sensitivity in comparison with culture and polymerase chain reaction. Specificity ranged from 91 percent to 100 percent, the concentrated acid-fast smear technique being the least specific. Nontuberculous mycobacteria were isolated three times more frequently in samples from indigenous patients than in those from non-indigenous patients. False-positive and false-negative polymerase chain reaction results were more common in the indigenous population. CONCLUSION: Positivity and isolation of nontuberculous mycobacteria in the acid-fast smear in conjunction with polymerase chain reaction positivity raise the following hypotheses: nontuberculous mycobacteria species with DNA regions homologous to, or even still possessing, the M. tuberculosis IS6110 exist in the Amazon; colonization of the oropharynx or of a tuberculous lesion accelerates the growth of the nontuberculous mycobacteria present in the sputum samples, making it impossible to isolate M. tuberculosis; A history of tuberculosis results in positivity for M. tuberculosis DNA. The absence of bacteriological positivity in the presence of polymerase chain reaction positivity raises questions regarding the inherent technical characteristics of the bacteriological methods or regarding patient history of tuberculosis.
Asunto(s)
Humanos , Indígenas Sudamericanos , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Técnicas Bacteriológicas , ADN Bacteriano/análisis , Mycobacterium tuberculosis/genética , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To evaluate the accuracy of bacteriological methods and of polymerase chain reaction (with primers specific for IS6110 of the Mycobacterium tuberculosis complex) in testing sputum samples from indigenous (Amerindian) and non-indigenous patients. METHODS: A total of 214 sputum samples (154 from indigenous patients and 60 from non-indigenous patients) were analyzed in order to determine the accuracy of smear microscopy (direct and concentrated versions) for acid-fast bacilli, culture, and polymerase chain reaction. RESULTS: Both microscopy methods presented low sensitivity in comparison with culture and polymerase chain reaction. Specificity ranged from 91% to 100%, the concentrated acid-fast smear technique being the least specific. Nontuberculous mycobacteria were isolated three times more frequently in samples from indigenous patients than in those from non-indigenous patients. False-positive and false-negative polymerase chain reaction results were more common in the indigenous population. CONCLUSION: Positivity and isolation of nontuberculous mycobacteria in the acid-fast smear in conjunction with polymerase chain reaction positivity raise the following hypotheses: nontuberculous mycobacteria species with DNA regions homologous to, or even still possessing, the M. tuberculosis IS6110 exist in the Amazon; colonization of the oropharynx or of a tuberculous lesion accelerates the growth of the nontuberculous mycobacteria present in the sputum samples, making it impossible to isolate M. tuberculosis; A history of tuberculosis results in positivity for M. tuberculosis DNA. The absence of bacteriological positivity in the presence of polymerase chain reaction positivity raises questions regarding the inherent technical characteristics of the bacteriological methods or regarding patient history of tuberculosis.
Asunto(s)
Indígenas Sudamericanos , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Esputo/microbiología , Tuberculosis Pulmonar/diagnóstico , Técnicas Bacteriológicas , ADN Bacteriano/análisis , Humanos , Mycobacterium tuberculosis/genética , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
INTRODUÇAO: Há diferentes primers sendo testados para a detecção do DNA do Mycobacterium tuberculosis. A acuidade da reação em cadeia da polimerase (PCR) depende da existência da seqüência alvo no bacilo e de os testes serem realizados em cepas isoladas ou em amostras clínicas. OBJETIVO: Verificar a presença das seqüências de DNA alvo mais relatadas na literatura para o diagnóstico da tuberculose em amostras clínicas usando como controle positivo as respectivas cepas de M. tuberculosis isoladas. MÉTODO: Oitenta e uma amostras clínicas de pacientes com suspeita de tuberculose foram submetidas à baciloscopia e cultivo. A técnica de PCR foi realizada nas amostras clínicas e cepas isoladas com primers específicos para os seguintes alvos: IS6110, 65 kDa, 38 kDa e MPB64. RESULTADOS: Em 24 amostras com baciloscopia e cultivo negativos, a PCR também foi negativa com todos os primers testados. Em 19 amostras com baciloscopia positiva e nas cepas isoladas obteve-se 100 por cento de resultados positivos nas PCR, exceto nas PCR em amostras clínicas com os primers para a seqüência MPB64 (89,4 por cento). Em 38 amostras com baciloscopia negativa e cultivo positivo, as PCR tiveram resultados variáveis, sendo que os primers específicos que amplificam o fragmento de 123 pb da seqüência IS6110 foram os que forneceram os maiores percentuais de positividade (92,1 por cento), concordância diagnóstica (0,9143), co-positividade (94,7 por cento) e co-negatividade (100 por cento). CONCLUSAO: As seqüências IS6110, 38 kDa, MPB64 e 65 kDa foram encontradas no genoma de todas as cepas de M. tuberculosis isoladas desses pacientes do Estado do Amazonas. O protocolo utilizado no processamento das amostras clínicas e os primers específicos utilizados para amplificação do fragmento de 123 pb da seqüência IS6110 demonstraram maior eficiência no diagnóstico da tuberculose pulmonar (paucibacilar) em comparação com a literatura.
Asunto(s)
Humanos , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Mycobacterium tuberculosis/genética , Cartilla de ADN/genética , Tuberculosis Pulmonar/diagnóstico , Genoma Bacteriano , Mycobacterium tuberculosis/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Sensibilidad y EspecificidadRESUMEN
Com o objetivo de verificar o percentual de conversao imunologica atraves da reacao de Mitsuda e realizar a analise de fatores envolvidos nesse processo, selecionou-se ex-pacientes portadores de hanseniase atendidos na Fundacao Alfredo da Matta (Manaus-AM), com as seguintes caracteristicas: forma clinica multibacilar, reacao de Mitsuda negativo no diagnostico, alta por cura no periodo de 1989 a 1993, sem tratamento especifico anterior e que fizeram uso de esquemas poliquimioterapicos (PQT) com regularidade. Os participantes foram dispostos em dois grupos conforme esquema PQT: 22 haviam feito uso do esquema da OMS (PQT/OMS), isto e, ate negativacao baciloscopica, e 24 utilizaram o esquema de duracao fixa (PQT/DF), com ingestacao de 24 doses. Todos foram reavaliados, em 1997, atraves de exame clinico-dermatoneurologico, baciloscopia da pele, grau de incapacidade e aplicacao de novo reacao de Mitsuda com posterior leitura. Constatou-se que entre os individuos classificados como portadores de hanseniase Virchowiana nao ocorreu nenhuma variacao de resposta imunologica celular, medida pela reacao de Mitsuda. Entretanto, nas demais formas e principalmente nos pacientes que fizeram uso de PQT/DF, a conversao ocorreu com maior frequencia a medida que o paciente, na classificacao de Ridley e Jopling, estava mais proximo do polo imunocompetente. Em relacao ao Indice Baciloscopico verificou-se que a negativacao baciloscopica precoce pode ter enterferido na conversao da Reacao de Mitsuda. A correlacao dos dados retrospectivos e os obtidos na reavalicao contemporanea permitiu concluir que estas conversoes, embora frequentes, nao estao relacionadas com o esquema poliquimioterapico utilizado, a presenca ou nao de reacao reversa ou com o grau de incapacidade induzido pela hanseniase.
Asunto(s)
Humanos , Lepromina/análisis , Lepromina/fisiología , Lepromina/genética , Lepromina/química , Lepra/fisiopatología , Lepra/inmunología , Lepra/rehabilitación , Lepra/terapia , Lepra/tratamiento farmacológico , Quimioterapia Combinada , Mycobacterium bovis/fisiología , Mycobacterium bovis/química , Mycobacterium leprae/fisiología , Mycobacterium leprae/genéticaRESUMEN
The Brazilian State of Amazonas has a high incidence of Tuberculosis, 91.4 in 10,000 habitants (SESAU, 1994) and resistant strains of Mycobacterium tuberculosis are frequently being found in the region (SALEM et.al, 1990). These problems have been associated with side effects caused by the antibiotics used to treat Tuberculosis, which have in turn been associated with treatment non-compliance (PATTISAPU, 1984). To resolve this problem a cost effective alternative treatment for Tuberculosis with few or no side effects, needs to be found. Amazonas has an abundance of plants, many of which are used by the lay population for medicinal purposes. A survey was carried out in five towns of the region, interviewing patients receiving treatment for Tuberculosis, to find out whether and which plants have been used to treat Tuberculosis. Results showed that the majority of patients in the sample had used medicinal plants before or after diagnosis of Tuberculoses. Thirteen different plants were recorded for this purpose. Chenopodium ambrosioides L., popularly known as Mastruz, was the most commonly used, followed by Caesalpinia ferrea Mart. Jucá and Spilanthes acmella D.C. Jambu. This study concentrates on Mastruz as it was used more frequently than the other medicinal plants. No significant effects on baciloscopy test results were found when Mastruz was used before diagnosis. In-vitro laboratory tests have also not shown any tuberculocidal effects for Mastruz. Further tests are being carried out on the other medicinal plants
Asunto(s)
Plantas Medicinales/uso terapéutico , Tuberculosis/terapiaRESUMEN
The Brazilian State of Amazonas has a high incidence of Tuberculosis, 91.4 in 10,000 habitants (SESAU, 1994) and resistant strains of Mycobacterium tuberculosis are frequently being found in the region (SALEM et.al, 1990). These problems have been associated with side effects caused by the antibiotics used to treat Tuberculosis, which have in rum been associated with treatment non-compliance (PATTISAPU, 1984). To resolve this problem a cost effective alternative treatment for Tuberculosis with few or no side effects, needs to be found. Amazonas has an abundance of plants, many of which are used by the lay population for medicinal purposes. A survey was carried out in five towns of the region, interviewing patients receiving treatment for Tuberculosis, to find out whether and which plants have been used to treat Tuberculosis. Results showed that the majority of patients in the sample had used medicinal plants before or after diagnosis of Tuberculoses. Thirteen different plants were recorded for this purpose. Chenopodium ambrosioides L, popularly known as Mastruz, was the most commonly used, followed by Caesalpinia ferrea Mart. Jucá and Spilanthes acmella DC. Jambu. This study concentrates on Mastruz as it was used more frequently than the other medicinal plants. No significant effects on baciloscopy test results were found when Mastruz was used before diagnosis. ln-vitro laboratory tests have also not shown any tuberculocidal effects for Mastruz. Further tests are being carried out on the other medicinal plants.
O Estado do Amazonas tem uma alta incidência de tuberculose, 91.4 por 10,000 habitantes (SESAU, 1994), e freqüentemente novas cepas de Mycobacterium tuberculosis resistentes a diversos antibióticos são encontrados (SALEM et.al, 1990). O abandono terapêutico está sendo relacionada aos efeitos colaterais desses antibióticos, contribui para este quadro (PATTISAPU, 1984). Assim faz-se necessário a descoberta de substâncias alternativas com baixo nível de efeitos colaterais negativos para o tratamento de tuberculose. Neste estado existe abundância de plantas utilizadas pela população no combate a várias doenças. Um levantamento foi feito com portadores de tuberculose emtratamento alopático em cinco municípios do estado do Amazonas, para descobrir quais são as plantas utilizadas por eles. Os resultados mostraram que a maioria dos pacientes entrevistados utilizavam plantas medicinas antes e/ou após tratamento alopático. Treze plantas foram citadas como plantas medicinais e utilizadas no tratamento de tuberculose. Chenopodium ambrosioides L., popularmente conhecida por mastruz, foi relatada como a planta mais utilizada, seguida pela Caesalpinia ferrea Mart., jucá e Spilanthes acmella D.C., jambu. Este estudo se concentra no mastruz por causa da baixa utilização das outras. Não encontramos um efeito significativo no comportamento baciloscópio quando o mastruz foi utilizada antes da diagnóstico. Testes de laboratórios "in-vitro" também não mostraram um resultado tubeculocida para mastruz. Outros testes estão sendo feito com as outras plantas citadas.