Lung clearance index short-term variability in cystic fibrosis. A
pre-post pulmonary exacerbation study.
Abstract
Background: Multiple Breath washout (MBW) represents an
important tool to detect early a possible pulmonary exacerbation
especially in Cystic Fibrosis (CF) disease. Lung clearance index (LCI)
is the most commonly reported multiple breath washout (MBW) index and in
the last years was used as management measure for evaluation. Our aim
was to analyze clinical utility of LCI index variability in pulmonary
exacerbation in CF. Methods: A single-center study was
conducted at CF Unit of Bambino Gesù Children’s Hospital among
hospitalized > 3 years patients for pulmonary exacerbations
and treated with antibiotic intravenous treatment for 14 days. MBW and
spirometry were evaluated within 72 hours of admission to hospital and
at the end of hospitalization. Descriptive analysis was conducted and
correlations between quantitative variables were investigated.
Results: Fifty-seven patients (M22/F35) with an average age
18.56 (± 8.54) years were enrolled. LCI 2.5 was significantly reduced at
the end of antibiotic treatment in both pediatric and adult populations
with an average improvement of -6% in 37/57 patients. 26/57 are stable
in LCI values. A significant elevation of +7.30% was found for FEV1%.
4/57 (7.02 %) had a significant deterioration in LCI values at the end
of IV antibiotic treatment. A positive good correlation among LCI 2.5
and Scond (rho= +0.615, p=0.000) and LCI 2.5 and Sacin (rho=+0.649,
p=0.000) and a negative strong correlation between FEV1% and LCI 2.5
were found in post treatment period. A better increase of LCI 2.5 in
< 18 years (-10.27% vs -4.57%) than adult was noticed.
Conclusions: LCI may have a role in the routine clinical care
of CF patients as a good tool to assess response to intravenous
antibiotic therapy.