Bronchiectasis

Key Features

Essentials of Diagnosis

• Chronic productive cough with dyspnea and wheezing

• Radiographic findings of dilated, thickened airways and scattered, irregular opacities

General Considerations

• A congenital or acquired disorder of large bronchi characterized by abnormal dilation and destruction of bronchial walls

• May be localized or diffuse

• May be caused by recurrent inflammation or infection

• Cystic fibrosis causes 50% of all cases

• Causes

  • Cystic fibrosis

  • Infection

    • Tuberculosis

    • Fungal

    • Abscess

    • Pneumonia

  • Abnormal lung defense mechanisms

    • Hypogammaglobulinemia

    • Common variable immunodeficiency

    • Selective IgA, IgM, and IgG subclass deficiency

    • Acquired immunodeficiency from cytotoxic drugs, AIDS, lymphoma, leukemia, plasma cell myeloma, chronic kidney disease, chronic liver disease

    • Alpha-1-antiprotease deficiency with cigarette smoking

    • Mucociliary clearance disorders (eg, immotile cilia syndrome)

    • Rheumatic disease (eg, rheumatoid arthritis)

  • Localized airway obstruction

Clinical Findings

Symptoms and Signs

• Chronic cough with production of copious, purulent sputum

• Recurrent pneumonia

• Hemoptysis

• Pleuritic chest pain

• Dyspnea and wheezing

• Weight loss and anemia common

• Persistent basilar crackles commonly found on examination

• Clubbing

  • Infrequent in mild cases

  • Present in severe disease

• Obstructive pulmonary dysfunction with hypoxemia seen in moderate or severe disease

• Haemophilus influenzae is the most common organism recovered from noncystic fibrosis patients with bronchiectasis

• Pseudomonas aeruginosa, Streptococcus pneumoniae, and Staphylococcus aureus are commonly identified; nontuberculous mycobacteria are seen less commonly

Differential Diagnosis

• Chronic obstructive pulmonary disease

• Asthma

• Bronchiolitis

• Allergic bronchopulmonary mycosis

Diagnosis

Laboratory Tests

• Sputum smear and culture for bacterial, mycobacterial, and fungal organisms

• Quantitative pilocarpine iontophoresis sweat test for sodium and chloride levels

• Quantitative immunoglobulins

• Alpha-1-antiprotease level

• Excluding patients with humoral immunodeficiencies, most patients have panhypergammaglobulinemia, reflecting an immune response to chronic airway infection

Imaging Studies

• Chest radiographs

  • Show dilated, thickened bronchi that may appear as "tram-tracks" or as ring-like markings

  • Scattered irregular opacities, atelectasis, and focal consolidation may be present

• High-resolution CT scanning is the diagnostic test of choice

Treatment

Medications

• Antibiotics should be used in acute exacerbations

• Empiric therapy for 10–14 days with

  • Amoxicillin or amoxicillin clavulanate (500 mg every 8 hours orally)

  • Ampicillin or tetracycline (250–500 mg four times daily orally)

  • Trimethoprim-sulfamethoxazole (160/800 mg every 12 hours orally)

  • Ciprofloxacin (500–750 mg twice daily orally)

• Sputum smears and cultures should guide therapy where possible

• Preventive or suppressive antibiotics are frequently given to patients with increased purulent sputum, although this practice is not guided by clinical trial data

  • Long-term macrolide therapy (azithromycin 500 mg three times a week orally for 6 months or 250 mg/day for 12 months) has been found to decrease the frequency of exacerbations compared to placebo

  • High-dose (3 g/day) amoxicillin orally or alternating cycles of amoxicillin or amoxicillin clavulanate, ampicillin or ...