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Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray
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Identificación de un brote de variante W de Mycobacterium tuberculosis a través de la epidemiología molecular basada
1Public Health Research Institute Tuberculosis Center, Department of Microbiology, New York University School of Medicine, NY 10016, USA.
JAMA
|December 28, 1999
Resumen
La tipificación molecular identificó un brote de tuberculosis por Mycobacterium no detectado previamente en Nueva Jersey. Este enfoque, utilizando huellas dactilares de ADN, reveló cepas distintas de la familia W y la demografía de los pacientes, ayudando a las intervenciones de salud pública específicas.
Área de la Ciencia:
- Epidemiología La epidemiología.
- Biología Molecular Biología Molecular
- Salud Pública La salud pública.
Sus antecedentes:
- La vigilancia convencional por sí sola es insuficiente para detectar brotes de Mycobacterium tuberculosis.
- La tipificación molecular ofrece un método más sensible para identificar la transmisión de la tuberculosis.
- Las variantes de la cepa W de M. tuberculosis de la ciudad de Nueva York fueron previamente identificadas en Nueva Jersey.
Objetivo del estudio:
- Para caracterizar la propagación de la familia W de cepas de M. tuberculosis en Nueva Jersey.
- Para utilizar la tipificación molecular y los datos de vigilancia para describir la diseminación de la cepa.
- Identificar patrones demográficos y geográficos específicos asociados con las cepas de la familia W.
Principales métodos:
- Estudio transversal basado en la población que analiza los casos de tuberculosis de enero de 1996 a septiembre de 1998.
- Las técnicas de tipificación molecular incluyeron las huellas dactilares de ADN IS6110, la tipificación PGRS, el spoligotipado y el análisis VNTR.
- La caracterización de la cepa se complementó con datos de vigilancia convencional.
Principales resultados:
- De 1207 aislamientos, 68 (6%) pertenecían a la familia W. Se identificaron dos grupos distintos (A y B) basados en los patrones de IS6110.
- Las cepas del grupo A (43 pacientes) estaban estrechamente relacionadas, mientras que las cepas del grupo B (25 pacientes) eran más diversas.
- Los pacientes del grupo A eran predominantemente nacidos en los Estados Unidos, negros, VIH positivos y residían en el noreste urbano de Nueva Jersey; los pacientes del grupo B eran principalmente asiáticos no nacidos en los Estados Unidos dispersos por todo el estado.
Conclusiones:
- Múltiples técnicas moleculares combinadas con datos de vigilancia identificaron con éxito un brote de tuberculosis no detectado previamente.
- El brote involucró una rama distinta del linaje filogenético de la familia W.
- La tipificación de cepas moleculares proporciona una estrategia proactiva para iniciar investigaciones de brotes, aumentando la vigilancia tradicional.
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