Pulmonary deposition of inhaled tobramycin prior to and after respiratory therapy and use of inhaled albuterol in cystic fibrosis patients colonized with Pseudomonas aeruginosa.
OBJECTIVE
To evaluate whether respiratory therapy followed by the use of inhaled albuterol modifies the pulmonary deposition of inhaled tobramycin in patients with cystic fibrosis (CF) and whether pulmonary deposition correlates with disease severity or genotype.


METHODS
A prospective study was carried out including patients with CF older than 6 years of age and colonized with Pseudomonas aeruginosa. Exclusion criteria were pulmonary exacerbation, changes in therapy between the study phases and FEV1 < 25%. All patients were submitted to pulmonary scintigraphy by means of a scintillation camera equipped with a low energy all purpose collimator in order to evaluate drug penetration following the administration of inhaled 99mTc-tobramycin, as well as to pulmonary perfusion with 99mTc-macroaggregated albumin (phase 1). One month later, the same procedure was performed following respiratory therapy and administration of inhaled albuterol (phase 2).


RESULTS
We included 24 patients (12 males) aged 5-27 years (mean +/- SD: 12.85 +/- 6.64 years). The Shwachman score (SS) was excellent/good in 8 patients, moderate/fair in 16 and poor in 0. Genotyping revealed that 7 patients were DeltaF508 homozygotes, 13 were DeltaF508 heterozygotes; and 4 presented other mutations. In all patients, lung deposition of tobramycin decreased in phase 2, especially in those with moderate/fair SS (p = 0.017) and in heterozygotes (p = 0.043).


CONCLUSIONS
The use of a respiratory therapy technique and the administration of inhaled albuterol immediately prior to the use of inhaled tobramycin decreased the pulmonary deposition of the latter in CF patients, and this reduction correlates with disease severity and genotype.
Grotta
Milena Baptistella
MB
State University at Campinas, School of Medical Sciences, Campinas, Brazil.
Etchebere
Elba Cristina de Sá Camargo
EC
Ribeiro
Antonio Fernando
AF
Romanato
Juliana
J
Ribeiro
Maria Angela Gonçalves de Oliveira
MA
Ribeiro
José Dirceu
JD
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D000420:Albuterol / Q000008:administration & dosage; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics*; D001993:Bronchodilator Agents / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000188:drug therapy / Q000378:metabolism / Q000628:therapy*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics; D004812:Epidemiologic Methods; D005260:Female; D005838:Genotype; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male; D009154:Mutation; D011552:Pseudomonas Infections / Q000188:drug therapy / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012138:Respiratory Therapy; D013667:Technetium / Q000493:pharmacokinetics; D014031:Tobramycin / Q000493:pharmacokinetics*; D055815:Young Adult
D000900:Anti-Bacterial Agents; D001993:Bronchodilator Agents; C505032:CFTR protein, human; D019275:Radiopharmaceuticals; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D013667:Technetium; D000420:Albuterol; D014031:Tobramycin