title: Mechanisms of increased epithelial lung clearance of DTPA in diffuse fibrosing alveolitis.
abstract: The aim of this study was to elucidate possible mechanisms of increased epithelial lung clearance in diffuse fibrosing alveolitis (DFA). We investigated the relationships between epithelial lung clearance as assessed by the clearance of aerosolized 99mTc-diethylene-triamine-penta-acetic acid (RC-DTPA), luminal alveolitis as assessed by bronchoalveolar lavage, and pulmonary function, in 30 nonsmokers with DFA. In 14 of these patients, RC-DTPA and lung function were determined before and during therapy with prednisolone (0.5 mg.kg-1 daily). RC-DTPA was higher in patients with DFA (4.45 +/- 2.50%.min-1) than in normal subjects (1.18 +/- 0.31%.min-1). RC-DTPA did not correlate with the number of alveolar neutrophils, but correlated positively with the number of alveolar lymphocytes, and negatively with vital capacity (VC). RC-DTPA decreased from 6.1 +/- 2.8 to 3.8 +/- 1.9%.min-1 with prednisolone. RC-DTPA before prednisolone correlated positively with the prednisolone-associated improvement in VC. We conclude that in patient with DFA, RC-DTPA is increased, and decreases but does not return to normal with corticosteroid therapy. Our data suggest that in DFA the increase in RC-DTPA could be related to the recoil-induced stretch of the respiratory epithelium and to alveolar lymphocytic inflammation.
authors.affiliation: Université de Paris René Descartes, Laboratoire de Biologie et Pharmacologie des Epithelia Respiratoires, France.
authors.forename: S
authors.initials: S
authors.lastname: Labrune
authors.forename: T
authors.initials: T
authors.lastname: Chinet
authors.forename: M A
authors.initials: MA
authors.lastname: Collignon
authors.forename: L
authors.initials: L
authors.lastname: Barritault
authors.forename: G J
authors.initials: GJ
authors.lastname: Huchon
mesh_terms: D000336:Aerosols; D004848:Epithelium / Q000502:physiology; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009079:Mucociliary Clearance; D011241:Prednisone / Q000627:therapeutic use; D011653:Pulmonary Diffusing Capacity; D011658:Pulmonary Fibrosis / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology*; D011877:Radionuclide Imaging; D016284:Technetium Tc 99m Pentetate; D014109:Total Lung Capacity; D014797:Vital Capacity
chemical_list: D000336:Aerosols; D011241:Prednisone; D016284:Technetium Tc 99m Pentetate