LIMBuS

Longitudinal Infant Multi-Breath washout Study (LIMBuS)

Lung Clearance Index (LCI) measured by multiple breath washout (MBW) has been shown to be a sensitive and non-invasive method of detecting early airways disease in infants with cystic fibrosis (CF). An abnormal measurement at a young age has been shown to track into later life, and could identify children that require more aggressive treatment earlier on. Currently however there is a lack of multi-centre data and of suitable scalable methodologies that can be used outside of highly specialised settings.



This is a multi-centre longitudinal observational study of this measurement, LCI, in children younger than 3 years with CF, with a healthy control group and a disease group of babies who were born early. A novel method for MBW will be used, which has been developed and previously assessed in a pilot study at RMCH.



We aim to show that LCI can be reliably measured across multiple centres using this method, with high rates of success and repeatability in the short term (2-3 months). We will also track any change in the children with CF and ex-premature babies in the longer term (12-18months). All parents will be consented prior to taking part in the study.



The first LCI measurements on children with CF will be undertaken as soon as possible after diagnosis or recruitment, then 2-4 months and 12-18 months later. Infants who were born early (currently well, with no supplemental oxygen requirement) will have LCI close to, and ideally before NICU discharge and then 12 months later. Healthy controls under 3 years of age with no other comorbidity or respiratory concerns will be seen once whilst being sedated for other investigations. The children will be sedated as per local protocol, but at lower doses than previously used and than routinely used for scans in order to allow quicker discharge.