Methods of assessing inflammation in the cystic fibrosis airways: pros and cons
| Parameter | Method | Advantage | Disadvantage |
|---|---|---|---|
| Lung function | Spirometry | Non-invasive Reproducible | Poor correlation with inflammation Does not localise disease Special equipment required for small children |
| Multiple breath washout (MBW) | Non-invasive and reproducible Identifies early small airway disease Applicable to small children | Requires special equipment Less sensitive in severe disease | |
| Respiratory samples | Sputum | Simple and accessible sample | Questionable reproducibility Limited correlation with clinical disease severity |
| Exhaled breath condensate (EBC) | Simple and non-invasive | Requires special equipment Questionable reproducibility | |
| Bronchoalveolar lavage (BAL) | Directlmeasurement of inflammation | Invasive Limited reproducibility Focal sampling | |
| Endobronchial biopsy (EBB) | Direct evaluation of level of inflammation | Invasive May not represent all the areas in the lungs Being used for research purposes only | |
| Imaging | High-resolution CT (HRCT) | Sensitive for early structural changes | Radiation exposure Does not distinguish old structural changes (scarring) from active inflammation |
| Positron emission tomography (PET-CT) | Directly measures neutrophilic activity May distinguish between active inflammation and old structural changes (scarring) | Radiation exposure Needs validation Being used for research purposes only |