Bronchiectasis
Marked by chronic abnormal dilation of the bronchi and destruction of the bronchial walls, bronchiectasis can occur throughout the tracheobronchial tree, or it may be confined to one segment or lobe. It’s usually bilateral and involves the basilar segments of the lower lobes.
The disease has three forms: cylindrical (fusiform), varicose, and saccular (cystic). It affects people of both sexes and all ages. With antibiotics available to treat acute respiratory tract infections, the incidence of bronchiectasis has fallen dramatically. Its incidence is high among Inuit populations in the Northern Hemisphere and the Maoris of New Zealand. Bronchiectasis is irreversible.
Causes
Bronchiectasis results from conditions associated with repeated damage to bronchial walls and with abnormal mucociliary clearance, which causes a breakdown of supporting tissue adjacent to the airways. Such conditions include:
cystic fibrosis
immune disorders (agammaglobulinemia, for example)
recurrent, inadequately treated bacterial respiratory tract infections
complications of measles, pneumonia, pertussis, or influenza
obstruction (by a foreign body, a tumor, or stenosis) with recurrent infection
inhalation of corrosive gas or repeated aspiration of gastric juices
In the patient with bronchiectasis, sputum stagnates in the dilated bronchi and leads to secondary infection, characterized by inflammation and leukocytic accumulations. Additional debris collects in and occludes the bronchi. Building pressure from the retained secretions induces mucosal injury.
Complications
Advanced bronchiectasis may produce chronic malnutrition and amyloidosis, right ventricular failure, and cor pulmonale.
Assessment
Patient complaints commonly include frequent bouts of pneumonia or a history of coughing up blood or blood-tinged sputum. The patient typically reports a chronic cough that produces copious, foul-smelling, mucopurulent secretions (up to several cups daily). He may also report dyspnea, weight loss, and malaise.
Inspection of the patient’s sputum may show a cloudy top layer, a central layer of clear saliva, and a heavy, thick, purulent bottom layer. In advanced disease, the patient may have clubbed fingers and toes and cyanotic nail beds.
If the patient also has a complicating condition, such as pneumonia or atelectasis, percussion may detect dullness over lung fields. Auscultation may reveal coarse crackles during inspiration over involved lobes or segments and occasional wheezes. With complicating atelectasis or pneumonia, you may hear diminished breath sounds during auscultation.
Diagnostic tests
