Understanding Inflammation, InFection and Interventions in Severe Exacerbations of Cystic Fibrosis

Participants will be recruited by staff within the care of UK CF centres. Initial discussions will occur either during routine outpatient reviews, telephone consultations or during admissions. Consent will take place prior to any other procedures. The investigators will provide the option of re-using baseline stable visits from the CF-Tracker study as stable visits for the UNIFIED-CF study. Consent to do this is specifically taken in UNIFIED, the investigators have added this as an option, and participants can opt to repeat the visit. Participants will be people living with cystic fibrosis being cared for at a participating centre in the UK. The study will enrol only those who are considered to be at risk for severe exacerbation in the next 24 months. Up to 300 participants will be recruited across 6 sites (expected number needed to get 125 exacerbations = 200). Participants will be assessed during a period of clinical stability. Participants taking part in another hub study (CF-Tracker, IRAS: 338539) where the same data and samples are being collected will not need to repeat this visit and will be given the option of re-using the outcomes from the previous visit, or participants can also opt to repeat the visit. If a participant has had a stable baseline visit but has not undergone any eligible CF exacerbations, they will be monitored for two years. They will be invited to a second stable baseline visit to repeat the same measurements after 12 months (range 10-14 months). If participants are admitted to one of the participating CF units for treatment of a pulmonary exacerbation, they will be eligible to take part in the Exacerbation Treatment arm of the UNIFIED study and will be monitored during their admission for up to a maximum of 17 days. In this arm, participants will undergo repeated assessments at pre-specified timepoints before and during their treatment at Pre-IV antibiotic baseline, Day 3 (range = day 2-4), Day 7 (range = day 6-8), Day 10 (range = day 9-12) and discharge day, alongside standard clinical care. A follow-up visit will take place after 6-14 weeks once the participant has returned to clinical stability. After this follow-up visit their will be no further participation.