Discussion: Bronchiectasis is defined as the abnormal dilatation of the proximal medium-sized bronchi (>2 mm in diameter) caused by destruction of the muscular and elastic components of bronchial walls. Damage to the muscular and elastic components of the bronchial wall is caused by the infectious organism and also by the inflammatory cytokines, nitric oxide, and neutrophilic proteases released in the host response to the organism. Additionally, peribronchial alveolar tissue may be damaged, resulting in diffuse peribronchial fibrosis. The result is abnormal bronchial dilatation with bronchial wall destruction and transmural inflammation.
Diseases associated with bronchiectasis are as follows:
Infection: Typical organisms include Klebsiella species, Staphylococcus aureus, Mycobacterium tuberculosis, Mycoplasma pneumoniae, nontuberculous mycobacteria, Mycobacterium avium-intracellulare complex, measles, pertussis, influenza, respiratory syncytial virus, herpes simplex virus, and certain types of adenovirus.
Bronchial obstruction: Obstruction occurs as a result of endobronchial tumors, broncholithiasis, bronchial stenosis resulting from infections, encroachment of hilar lymph nodes, and foreign body aspiration.
Cystic fibrosis,Young syndrome,Primary ciliary dyskinesia,Allergic bronchopulmonary aspergillosis,
Immunodeficiency states: The most common congenital conditions involve B-lymphocyte functions, specifically hypogammaglobulinemia. An aggressive form of bronchiectasis has been described in patients with AIDS.
Congenital anatomic defects
Bronchopulmonary sequestration
Williams-Campbell syndrome (congenital cartilage deficiency)
Mounier-Kuhn syndrome (tracheobronchomegaly)
Swyer-James syndrome (unilateral hyperlucent lung)
Yellow nail syndrome
a1-Antitrypsin deficiency
Lung and bone marrow transplants
Rheumatoid arthritis and Sjögren syndrome
Traction bronchiectasis associated with pulmonary fibrosis
