Evaluation of the Lung Clearance Index
Condition: Cystic Fibrosis
MeSH terms: Cystic Fibrosis; Fibrosis
Study type: Interventional

Summary: 
      The purpose of this study is to determine the efficacy of a non invasive method of detecting
      the pulmonary disease in order to initiate treatment against cystic fibrosis as soon as
      possible.

      Moreover this screening procedure permits to note the improvement following the treatment and
      to choose the optimal treatment in term of efficacy.
    

Detailed description: 
      It is mandatory to detect as early as possible lung CF disease in the young child with CF to
      initiate active therapies limiting irreversible lesions. Lung Clearance Index (LCI) which
      evaluates gas clearance from the alveolar volume is an easy to-do technique in pre-school
      children.

      Main objective To evaluate correlation between LCI and thoracic low dose computed
      tomodensitometry (CT) endpoints at initial visit Secondary objectives

        1. To evaluate correlation between LCI and respiratory function measurements at each visit

        2. To evaluate correlation between the evolution of LCI and respiratory function endpoints
           and the evolution of CT only for the children for whom a thoracic low dose CT is
           requested by their referent doctor after two years.

        3. To evaluate LCI predictive value for respiratory function 2 years later in preschool
           children.

      This is a prospective multicenter cohort study. Study visits will be performed each year
      during the annual check up for normal follow up of the child.

      Initial visit (Visit 1) takes place during an annual check-up during which a low dose CT was
      prescribed. It will include following tests: LCI, Lung function tests (LFTs) performed
      according to age (forced volumes and flows, plethysmographic specific airway resistances and
      interrupter resistances), and a low dose CT scan performed according a standardized protocol.

      Visit 2 will be performed 12 ± 3 months later and will include following tests: LCI , LFTs.

      Visit 3 will be performed 24 ± 3 months later and will include following tests: LCI , LFTs
      and, if judged necessary by the child's referent doctor, a low dose CT scan performed
      according to a standardized protocol.

      Anthropometric data, infection history, treatment will be collected at each visit.

      Recruiting period: 1 year Study period: 2 years per patient, 3 years as a whole LCI will help
      to evaluate early ventilation inhomogeneity due to small bronchi abnormalities in young
      children with CF. Concordance between LCI and CT endpoints evaluation will help to define the
      frequency of lung CT administration in young CF children. Predictive value for later abnormal
      lung function development will be evaluated. This will help to detect the children at risk to
      develop abnormal lung function and to target those requiring active treatment. Finally this
      endpoint will be very valuable in the future therapeutic trials for CFTR correctors or
      potentiators.
    

Intervention name(s): Lung clearance index determination
Intervention type(s): Other
Intervention description(s): Lung clearance index determination
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Screening
Keywords: Cystic fibrosis,; lung clearance index,; pulmonary function