학술논문

Airway inflammation and mannitol challenge test in COPD
Document Type
Academic Journal
Source
Respiratory Research. January 18, 2011, Vol. 12 Issue 1037
Subject
Inflammation
Respiratory agents
Lung diseases, Obstructive
Language
English
ISSN
1465-9921
Abstract
Background Eosinophilic airway inflammation has successfully been used to tailor anti-inflammatory therapy in chronic obstructive pulmonary disease (COPD). Airway hyperresponsiveness (AHR) by indirect challenges is associated with airway inflammation. We hypothesized that AHR to inhaled mannitol captures eosinophilia in induced sputum in COPD. Methods Twenty-eight patients (age 58 [+ or -] 7.8 yr, packyears 40 [+ or -] 15.5, post-bronchodilator FEV.sub.1 77 [+ or -] 14.0%predicted, no inhaled steroids [greater than or equai to]4 wks) with mild-moderate COPD (GOLD I-II) completed two randomized visits with hypertonic saline-induced sputum and mannitol challenge (including sputum collection). AHR to mannitol was expressed as response-dose-ratio (RDR) and related to cell counts, ECP, MPO and IL-8 levels in sputum. Results There was a positive correlation between RDR to mannitol and eosinophil numbers (r = 0.47, p = 0.03) and level of IL-8 (r = 0.46, p = 0.04) in hypertonic saline-induced sputum. Furthermore, significant correlations were found between RDR and eosinophil numbers (r = 0.71, p = 0.001), level of ECP (r = 0.72, p = 0.001), IL-8 (r = 0.57, p = 0.015) and MPO (r = 0.64, p = 0.007) in sputum collected after mannitol challenge. ROC-curves showed 60% sensitivity and 100% specificity of RDR for >2.5% eosinophils in mannitol-induced sputum. Conclusions In mild-moderate COPD mannitol hyperresponsiveness is associated with biomarkers of airway inflammation. The high specificity of mannitol challenge suggests that the test is particularly suitable to exclude eosinophilic airways inflammation, which may facilitate individualized treatment in COPD. Trial registration Netherlands Trial Register (NTR): NTR1283
Author(s): Selma B de Nijs[sup.1] , Niki Fens[sup.1] , Rene Lutter[sup.1,2] , Erica Dijkers[sup.1] , Frans H Krouwels[sup.3] , Barbara S Smids-Dierdorp[sup.1,2] , Reindert P van Steenwijk[sup.1] and Peter J [...]