TAAI Erasmus Research Initiative to Fight CF: Monitoring Inflammation in CF Lung Disease Into a New Era

Progressive destruction of the lungs is the main cause of shortened life expectancy in people with cystic fibrosis (pwCF). Inflammation and respiratory infections play a key role in CF lung disease. Previous studies have shown that an increase in inflammatory markers predicts structural lung damage. Close monitoring of pwCF is crucial to adequately provide optimal care. Pulmonary management for pwCF involves treating infections and exacerbations and promoting exercise and mucociliary clearance to slow or prevent structural lung damage. To evaluate the treatment and incite timely interventions it is important for the pulmonary physician to be well-informed about the condition of the lungs. The main monitoring tools in regular CF care are lung function, sputum cultures, symptom reporting and more recently imaging by chest computed tomography (CT-scan) or magnetic resonance imaging (MRI). Strangely enough, there are currently no monitoring tools used in clinics to measure inflammation in the lung, although this is a main factor for progressive lung disease. New highly effective modulator therapy (HEMT) such as elexacaftor/tezacaftor/ivacaftor \[ETI, Kaftrio®\] is transforming CF treatment, vastly improving lung function and reducing exacerbations. Initial CFTR modulators like ivacaftor and lumacaftor/ivacaftor also improved lung function and reduced exacerbations, but studies showed that lung inflammation was still present. The long-term impact of ETI and its effect on inflammation is not yet known. Thus, monitoring pwCF on HEMT may be different from before, as lung damage seen on chest CT will be less apparent and lung function will improve considerably, therefore not being adequate markers for subtle changes in the lungs. Thus, the focus of monitoring in the era of highly effective CFTR modulators needs to change preferably focusing on measuring lung inflammation. An ideal monitoring tool for lung inflammation in pwCF should be non-invasive, efficient, and provid