RESUMEN
Introducción y objetivo: Los aislamientos de micobacterias no tuberculosas (MNT) son cada vez más frecuentes. El objetivo principal de nuestro estudio fue conocer el número y la variedad de especies de MNT en nuestra región, su distribución según el origen de la muestra, y la edad y sexo de los pacientes; asimismo, analizar pormenorizadamente los aislamientos clínicamente significativos. Metodología: Estudio prospectivo que incluye todas las MNT aisladas en Asturias durante el período 2005-2012. Las muestras se procesaron siguiendo directrices internacionalmente aceptadas. Para el tratamiento estadístico de los datos se utilizaron tablas de contingencia 2 × 2 aplicando el test exacto de Fisher. Resultados: Se aislaron 3.284 micobacterias: 1.499 Mycobacterium tuberculosis complex (MTB) y 1.785 MNT. A lo largo del estudio se incrementaron los aislamientos de MNT y se redujeron los de MTB. Los aislamientos de MNT fueron más numerosos en hombres que en mujeres (p <0,001). M. gordonae, la especie más frecuentemente aislada, no originó enfermedad en ningún caso. El aislamiento fue clínicamente significativo en 212 pacientes (17,1%), siendo M. kansasii y M. avium las especies que más frecuentemente causaron enfermedad. La diferencia de aislamientos de M. kansasii entre mujeres y hombres fue estadísticamente significativa (p < 0,01). Conclusiones: En nuestro estudio, los aislamientos de MNT se incrementaron un 35%, frente a un descenso del 21% de los casos de MTB. Tanto los aislamientos de MNT como los casos clínicamente significativos fueron más frecuentes en hombres. Solo un 17,1% de las MNT aisladas, principalmente M. avium complex (MAC) y M. kansasii, ocasionaron enfermedad
Introduction and objective: Non-tuberculous mycobacteria (NTM) isolates are becoming more common. The main objective of our study was to establish the number and diversity of NTM species in our region and their distribution according to the source sample, age and gender of the patients, and to analyse clinically significant isolates. Methodology: Prospective study of all NTM isolated in Asturias from 2005 to 2012. Samples were processed following internationally accepted guidelines. Statistical analysis was based on Fisher's exact test for 2 × 2 contingency tables. Results: A total of 3,284 mycobacteria were isolated: 1,499 Mycobacterium tuberculosis complex (MTB) and 1,785 NTM. During the study, NTM isolation rates increased while MTB isolation decreased. NTM were more frequent in men (P < .001). M. gordonae was the most frequently isolated species but did not cause disease in any case. NTM isolates from 212 patients were associated with clinically significant disease (17.1%). M. kansasii and M. avium were most commonly associated with disease. The number of M. kansasii isolates from men was statistically significant (P < .01). Conclusions: In our study, NTM isolates increased by 35%, compared with a 21% decline in cases of MTB. Both isolation of NTM and clinically significant cases were more common in men. Only 17.1% of NTM isolates were associated with disease, most commonly M. avium complex and M. kansasii
Asunto(s)
Humanos , Mycobacterium/aislamiento & purificación , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Micobacterias no Tuberculosas/patogenicidad , Estudios Prospectivos , Infecciones por Mycobacterium/epidemiología , Enfermedades Transmisibles Emergentes/epidemiología , Mycobacterium kansasii/patogenicidad , Mycobacterium avium/patogenicidad , Mycobacterium tuberculosis/patogenicidadRESUMEN
INTRODUCTION AND OBJECTIVE: Non-tuberculous mycobacteria (NTM) isolates are becoming more common. The main objective of our study was to establish the number and diversity of NTM species in our region and their distribution according to the source sample, age and gender of the patients, and to analyse clinically significant isolates. METHODOLOGY: Prospective study of all NTM isolated in Asturias from 2005 to 2012. Samples were processed following internationally accepted guidelines. Statistical analysis was based on Fisher's exact test for 2×2 contingency tables. RESULTS: A total of 3,284 mycobacteria were isolated: 1,499 Mycobacterium tuberculosis complex (MTB) and 1,785 NTM.During the study, NTM isolation rates increased while MTB isolation decreased. NTM were more frequent in men (P<.001). M.gordonae was the most frequently isolated species but did not cause disease in any case. NTM isolates from 212 patients were associated with clinically significant disease (17.1%). M.kansasii and M.avium were most commonly associated with disease. The number of M.kansasii isolates from men was statistically significant (P<.01). CONCLUSIONS: In our study, NTM isolates increased by 35%, compared with a 21% decline in cases of MTB. Both isolation of NTM and clinically significant cases were more common in men. Only 17.1% of NTM isolates were associated with disease, most commonly M.avium complex and M.kansasii.
Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Micobacterias no Tuberculosas/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Tipificación Bacteriana , Niño , Preescolar , Enfermedades Transmisibles Emergentes/microbiología , Heces/microbiología , Femenino , Hospitales Públicos , Humanos , Lactante , Ganglios Linfáticos/microbiología , Masculino , Persona de Mediana Edad , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas/clasificación , Estudios Prospectivos , Sistema Respiratorio/microbiología , Piel/microbiología , España/epidemiología , Especificidad de la Especie , Orina/microbiología , Adulto JovenRESUMEN
BACKGROUND: Despite major public health initiatives and the existence of efficacious treatment regimes, tuberculosis (TB) remains a threat, particularly in resource-limited settings. A significant part of the problem is the difficulty of rapidly identifying infected individuals, and as a result, there has been renewed interest in developing better diagnostics for infection or disease caused by Mycobacterium tuberculosis. Many of the existing tools, however, have limitations such as poor sensitivity or specificity, or the need for well-equipped laboratories to function effectively. Serodiagnostic approaches in particular have long drawn attention, due to their potential utility in large field studies, particularly in resource-poor settings. Unfortunately none of the serodiagnostic approaches have so far proven useful under field conditions. RESULTS: We screened a large panel of antigens with serodiagnostic potential by ELISA and selected a subpanel that was strongly and broadly recognised by TB patients, but not by controls. These antigens were then formulated into a simple immuno-chromatographic lateral flow assay format, suitable for field use, and tested against panels of plasma and blood samples from individuals with different clinical status (confirmed TB patients, household contacts, and apparently healthy community controls), recruited from Ethiopia (a highly TB-endemic country) and Turkey (a TB meso-endemic country). While specificity was good (97-100% in non TB-endemic controls), the sensitivity was not as high as expected (46-54% in pulmonary TB, 25-29% in extra-pulmonary TB). CONCLUSIONS: Though below the level of sensitivity the consortium had set for commercial development, the assay specifically identified M. tuberculosis-infected individuals, and provides a valuable proof of concept.