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Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán

2000, Número 3

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Rev Biomed 2000; 11 (3)


Helicobacter pylori: Factores de virulencia, patología y diagnóstico

Rivas-Traverso F, Hernández F

Idioma: Español
Referencias bibliográficas: 148
Paginas: 187-205
Archivo PDF: 123.18 Kb.


RESUMEN

En este artículo revisamos la evidencia concerniente a los factores de virulencia de Helicobacter pylori, la principal causa de gastritis, úlceras pépticas y algunos tipos de neoplasias. También se hace un resumen de los hallazgos acerca de los posibles modos de transmisión, incluyendo las siguientes rutas: oral-oral, gastro-oral y fecaloral. La principal evidencia para cada una de esas rutas consisten el aislamiento e identificación del DNA de H pylori en saliva, placa dental, heces y en el agua. También se describen algunos factores de virulencia tales como a) la actividad de ureasa que promueve la liberación de amonia la cual puede inducir daño en el epitelio gástrico; b) adhesinas bacterianas que son fundamentales para el proceso de colonización; c) hemaglutininas las cuales inducen auto-anticuerpos debido a su similaridad bioquímica con antígenos presentes en los grupos sanguíneos; d) presencia del gen asociado a la vacuolización (vacA) y del gen asociado a la citotoxicidad (cagA) que correlaciona con cepas virulentas que exhiben actividad de citotóxica.
El perfil de la distribución epidemiológica a nivel mundial de H. pylori está correlacionado con la distribución del cáncer gástrico.
También describimos en este artículo la metodología para la diagnosis de H. pylori mediante el cultivo, incluyendo un método económico que genera la atmósfera microaerofílica requerida, un método de ureasa rápido y de bajo costo, así como la visualización de bacterias curvas en frotis de biopsias gástricas.


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