Table 1

Methods of assessing inflammation in the cystic fibrosis airways: pros and cons

ParameterMethod AdvantageDisadvantage
Lung functionSpirometryNon-invasive
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 samplesSputumSimple and accessible sampleQuestionable reproducibility
Limited correlation with clinical disease severity
Exhaled breath condensate (EBC)Simple and non-invasiveRequires special equipment
Questionable reproducibility
Bronchoalveolar lavage (BAL)Directlmeasurement of inflammationInvasive
Limited reproducibility
Focal sampling
Endobronchial biopsy (EBB)Direct evaluation of level of inflammationInvasive
May not represent all the areas in the lungs
Being used for research purposes only
ImagingHigh-resolution CT (HRCT)Sensitive for early structural changesRadiation 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