European Respiratory Society Annual Congress 2013

European Respiratory Society
Annual Congress 2013
Abstract Number: 5038
Publication Number: P2114
Abstract Group: 7.3. Cystic Fibrosis
Keyword 1: Imaging Keyword 2: Bacteria Keyword 3: No keyword
Title: Airway surface liquid concentrations of aztreonam lysine for inhalation in children with cystic fibrosis:
A modeling study
Mr. Cedric 13535 Van Holsbeke [email protected] 1, Ms. Aukje 13565 Bos
[email protected] MD 2, Dr. Wim 13536 Vos [email protected] 1, Dr. Jan 13537 De Backer
[email protected] 1, Dr. Hettie 13566 Janssens [email protected] MD 2 and Prof. Dr
Harm 13572 Tiddens [email protected] MD 2,3. 1 Respiratory, FluidDA Nv, Kontich, Belgium ; 2
Department of Pediatric Pulmonology and Allergology, Erasmus Medical Center-Sophia Children's Hospital,
Rotterdam, Netherlands and 3 Department of Pediatric Radiology, Erasmus Medical Center-Sophia
Children's Hospital, Rotterdam, Netherlands .
Body: Introduction The mechanics of inhaled antibiotics in obstructed airways are not well known. It is
possible that local areas with concentration below the minimal inhibitory concentration (10xMIC90, 128µg/ml
for P. Aeruginosa) exist, causing undertreated parts of the lung. To optimize inhaled therapy, knowledge
about antibiotic concentrations throughout the lung should be known. Local deposition characteristics of
inhaled Aztreonam lysine (AZLI) were simulated using Functional Respiratory Imaging. Methods Airways
and lungs were segmented from a retrospective dataset of 40 in- and expiratory CT-scans of children with
cystic fibrosis (CF) between 5 and 17 years. FRI simulations were performed that simulated the nebulisation
of 75mg AZLI through PARI eFlow® with minimal/median/maximal reported aerodynamic diameters
(MMAD) and different thicknesses of airway surface liquid (ASL). Figure 1 shows local concentrations in the
central airways and lung.
Results In Figure 2, it is shown how many lobes are being undertreated.
Conclusion Parts of the CF-lung receive concentrations < 10xMIC90 with inhaled antibiotics, such as AZLI.