Article

Fisiopatología de la fibrosis quística

DOI: 10.1159/000098085

ABSTRACT ExtractoEl conocimiento del desarrollo de la neumopatía en la fibrosis quística (FQ) ha sido la meta perseguida durante varias décadas. Con la clonación del gen regulador de conductancia transmembránica de la FQ (RTFQ) y otros avances en el estudio de la biología de los tejidos epiteliales de las vías respiratorias, se dispone de un cuadro mucho más nítido de la fisiopatología de la enfermedad. Nuestras mejores pruebas señalan la desregulación del transporte de iones como trastorno subyacente, causante de la depleción del volumen de líquido de la superficie de las vías respiratorias, es decir, la deshidratación, y un deterioro asociado de la depuración de moco. A su vez, la mucostasis predispone al pulmón de la FQ a la infección bacteriana, que rápidamente adquiere cronicidad debido a la propia naturaleza de las secreciones de la FQ. La respuesta inflamatoria neutrofílica, no resolutiva, a esta infección crónica causa a su vez una lesión progresiva y permanente de las vías respiratorias, de tal modo que la bronquiectasia y la insuficiencia respiratoria son los procesos corrientes de la neumopatía de la FQ en su fase terminal. El desarrollo de nuevos tratamientos que aborden el trastorno subyacente de la deshidratación de las vías respiratorias constituye la esperanza de prevención de esta cascada de acontecimientos.

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