membranous laryngotracheobronchitis ( membranous croup ) , not previously described as a distinct entity , is characterized by diffuse inflammation of the larynx , trachea , and bronchi with adherent or semiadherent mucopurulent membranes in the subglottic trachea ( conus elasticus ) and in the upper trachea distal to the conus elasticus .
C0010380
croup
C0023078
larynx