Internally Peer Reviewed Introduction Viral infection causing subglottic and tracheal swelling. Most common cause of stridor in children. More common in fall and winter. Pathophysiology Virus invades epithelium of the nasopharynx with local spread to larynx and trachea.
Epithelial damage causes mucous production and loss of ciliary function.
Edema of the subglottic larynx. A small amount of edema within the ring of the cricoid cartilage leads to a large decrease in air flow. Fibrinous exudate partially occludes the lumen of the trachea. Clinical Manifestations Insidious onset of fever, coryza, cough and sore throat. Stridor and barking cough develop on day 2-3.