Bronchiectasis pathophysiology
Bronchiectasis Microchapters |
Diagnosis |
---|
Treatment |
Case Studies |
Bronchiectasis pathophysiology On the Web |
American Roentgen Ray Society Images of Bronchiectasis pathophysiology |
Risk calculators and risk factors for Bronchiectasis pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Bronchiectasis involves bronchi that are dilated, inflamed, and easily collapsible. This results in airflow obstruction and impaired clearance of secretions.
Pathophysiology
Dilation of the bronchial walls results in airflow obstruction and impaired clearance of secretions because the dilated areas interrupt normal air pressure of the bronchial tubes, causing sputum to pool inside the dilated areas instead of being pushed upward[1]. The pooled sputum provides an environment conducive to the growth of infectious pathogens, and these areas of the lungs are thus very vulnerable to infection. The more infections that the lungs experience, the more damaged the lung tissue and alveoli become. When this happens, the bronchial tubes become more inelastic and dilated, which creates a perpetual, destructive cycle within this disease.
There are three types of bronchiectasis, varying by level of severity. Fusiform (cylindrical) bronchiectasis (the most common type) refers to mildly inflamed bronchi that fail to taper distally. In varicose bronchiectasis, the bronchial walls appear beaded, because areas of dilation are mixed with areas of constriction. Saccular (cystic) bronchiectasis is characterized by severe, irreversible ballooning of the bronchi peripherally, with or without air-fluid levels.[2] Chronic productive cough is prominent, occurring in up to 90% of patients with bronchiectasis. Sputum is produced on a daily basis in 76% of patients.