SESSION TITLE: Asthma
SESSION TYPE: Original Investigation Slide
PRESENTED ON: Wednesday, October 29, 2014 at 08:45 AM - 10:00 AM
PURPOSE: Severe asthma requires treatment with high dose inhaled corticosteroids plus a second controller to prevent which remain uncontrolled despite this therapy. It has been previously demonstrated exhaled NO (FeNO) is higher during a deterioration in asthma control and would be related with eosinophilic inflammation. Despite potential utility as a biomarker, the induced sputum eosinophil count measurements has not been widely recommended by ERS/ATS guidelines. The aim of this study was to determine whether levels of FeNO could be related with the sputum eosinophils in different phenotypes of severe and mild to moderate asthma.
METHODS: We performed a study of admissions to a respiratory hospital. We collected sputum samples from 6 patients with mild to moderate asthma (MMA) female/male: 3/3, with an average of age of 33.5±5.4 years old; 30 patients with difficult to treatment severe asthma (DTTSA), female/male: 15/15, with 37,4±2.6 years old and 8 patients with treatment resistance severe asthma (TRSA), female/male: 7/1, with 51.4±3.8 years old. Patients were diagnosed according to World Health Organization criteria. Sputum samples were processed with 0.1% dithiotreitol, cytospined and eosinophils were counted. All subjects underwent exhaled nitric oxide measure. Data were analyzed with Kruskall Wallis test and linear regression analyses.
RESULTS: We found a significant relationship between FeNO and the percentage of eosinophils only in TRSA group (Spearman r=0.7 and p<0.05). Moreover, we found an increase of eosinophils in TRSA patients respect to DTTSA and MMA groups (12.4±5.8 % vs 6.4±1.4% and 4.2±2.4 % respectively). We observed persistent eosinophilia in TRSA despite higher doses of inhaled corticosteroid therapy.
CONCLUSIONS: Our results have shown that FeNO measured could be related with the increase of sputum eosinophils in TRSA but not in DTTSA or MMA.
CLINICAL IMPLICATIONS: Sputum is a non-invasive technique for the assessment of bronchial inflammation, and for detecting the cellular and inflammatory profile. The observations presented in this abstract could be important for understaning the role of FeNo and eosinophils as biomarkers in different phenotypes of asthma.
DISCLOSURE: The following authors have nothing to disclose: Glenda Ernst, Fabian Caro, Martín Fernandez, Guillermo Menga, Daniel Colodenco, Eduardo Schiavi
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