Definition
- An irreversible dilatation and destruction of the bronchi
- Results in airflow obstruction and impaired clearance of secretions
- Enhances susceptibility to bronchial infection and increases inflammatory reaction which causes further lung damage
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Primary Infections
- Necrotizing infections that are not treated properly or untreated are a common cause of bronchiectasis in developing countries
- Typical offending organisms include Klebsiella sp, Staphylococcus aureus, Mycobacterium tuberculosis, Mycoplasma pneumoniae, non-tuberculous mycobacteria, measles, pertussis, influenza, herpes simplex and certain types of adenovirus
- Mycobacterium avium complex (MAC) has propensity to occur in patients who are immunocompetent
- Patients with chronic Pseudomonas aeruginosa colonization are at higher risk for complications
- Focal post-obstructive bronchiectasis may occur in endobronchial tumors, broncholithiasis, bronchial stenosis from infections, encroachment of hilar lymph nodes and foreign body aspiration
- Recurrent aspiration caused by gastroesophageal reflux disease (GERD) or dysphagia may be the cause of bronchiectasis in 1-11.3% of adult patients
- In adults, foreign body aspiration may occur with altered mental status and when food is not chewed
- Chicken bone fragments may be the cause of lower respiratory tract obstruction in Chinese people from eating cooked meat on the bone
- Typically rare in non-white races
- Autosomal recessive multi-system disorder affecting the chloride transport system in exocrine tissues
- Bronchiectasis is the major pulmonary finding of this disease, occurring secondary to mucous-plugged proximal airways and chronic respiratory infection
- Rare but can cause poor mucociliary clearance, recurrent respiratory infections and bronchiectasis
- Kartagener’s syndrome which is characterized by situs inversus, bronchiectasis, chronic sinusitis with immotile cilia
- Hypersensitivity reaction to inhaled Aspergillus antigen that is characterized by bronchospasm, bronchiectasis, and immunologic evidence of a reaction to Aspergillus sp
- Bronchiectasis is secondary to airway plugs of viscid secretions containing hyphae of Aspergillus sp
- Computed tomography (CT) scan of chest reveals central airway bronchiectasis
- Syndrome clinically similar to CF
- Patients have the triad of bronchiectasis, sinusitis and obstructive azoospermia
- Congenital or acquired immunodeficiency usually present with repeated sinus or pulmonary infections
- Bronchiectasis in acquired immunodeficiency syndrome (AIDS) has occurred with or without obvious preceding pulmonary infections
- Pathogenesis of bronchiectasis in these conditions is unclear and may represent only coincidental findings
- Patients with A1AT deficiency make-up <1% of the population with bronchiectasis
- Individuals whose etiology is connected to rheumatoid arthritis account for only 2-5% of patients with bronchiectasis
- Distortion of the airways secondary to distortion of the lung parenchyma from pulmonary fibrosis
Signs and Symptoms
- Cough with chronic sputum production with recurring infective exacerbations and hemoptysis
- Rattly cough producing sputum after colds only
- Sputum production of <10 mL/day
- Change of position may cause sputum production
- May cause mild hemoptysis
- Well patient
- Constant rattly cough
- Sputum production of 10-150 mL/day
- Sputum production most of the time
- Occasional hemoptysis
- May have foul smelling breath
- Usually well patient
- Production of large volumes of sputum
- Sputum production of >150 mL/day
- Occasional pleural pain and hemoptysis
- Usually unwell patient
- May develop respiratory failure
Symptoms of Exacerbation
- Recognizing acute exacerbation generally depends upon symptomatic changes rather than any specific lab result
- Identification of acute exacerbation may be difficult since the onset may be gradual with sputum volume increasing slowly over months
- Acute bacterial infections are usually indicated by increased sputum production with enhanced viscidity, often with lassitude, shortness of breath and pleuritic chest pain
- Fever and chills are generally absent and chest X-ray rarely shows new infiltrates
