What laboratory tests are indicated for bronchiectasis?

From the Guidelines

Bronchiectasis patients should undergo a panel of investigations, including full blood count, serum total IgE, assessment of sensitisation to A. fumigatus, serum IgG, IgA, and IgM, and sputum cultures for routine and mycobacterial culture, as recommended by the British Thoracic Society guideline for bronchiectasis in adults 1. The goal of these investigations is to establish the underlying cause of bronchiectasis, which is essential for proper management and treatment.

• Key laboratory tests for bronchiectasis include:
  • Full blood count to assess for infection and inflammation
  • Serum immunoglobulins (total IgG, IgA, and IgM) to check for immunodeficiency
  • Sputum culture to identify pathogens, including mycobacterial culture if non-tuberculous mycobacteria are suspected
  • Testing for allergic bronchopulmonary aspergillosis (ABPA)
  • Measurement of baseline specific antibody levels against capsular polysaccharides of S. pneumoniae to investigate for specific antibody deficiency
• Additional tests may be appropriate in response to specific clinical features, such as testing for cystic fibrosis or primary ciliary dyskinesia (PCD) in patients with supporting clinical features 1.
• The European Respiratory Society guidelines for the management of adult bronchiectasis also suggest a minimum bundle of aetiological tests, including differential blood count, serum immunoglobulins, and testing for ABPA 1.
• However, the British Thoracic Society guideline provides a more comprehensive list of recommended investigations, making it the preferred choice for guiding clinical practice in this area 1.

From the Research

Laboratory Tests for Bronchiectasis

The following laboratory tests are indicated for bronchiectasis:

• Immunoglobulins: to detect underlying immunodeficiency conditions 2
• Testing for allergic bronchopulmonary aspergillosis: to identify fungal infections that may be contributing to the disease 2
• Full blood count: to evaluate for signs of infection or inflammation 2
• Sputum cultures: to identify bacterial pathogens such as Pseudomonas aeruginosa, which is commonly associated with bronchiectasis 3, 4, 5
• High-resolution computed tomography (HRCT) features: to evaluate the extent and severity of bronchiectasis and identify underlying causes 2, 5

Additional Testing

Additional testing may be recommended based on the clinical history, radiological features, and severity of disease, including:

• Testing for autoimmune conditions or genetic disorders that may be contributing to the disease 6
• Evaluation of lung function using spirometry or other tests to assess the severity of lung damage 6, 5
• Molecular diagnostics or biomarkers to help guide personalized medicine approaches 4, 6