October 2013, Vol 144, No. 4_MeetingAbstracts Allergy and Airway | October 2013
Levels of IL-8 and IL17-A in Sputum Samples From Severe Asthma Patients Glenda Ernst, MS; Auteri Santiago, MD; Fabian Caro, MD; Daniel Colodenco, MD; Ricardo Del Olmo, MD; Martin Fernandez, MD; Jorge Geffner, PhD; Dora Lombardi, MD; Guillermo Menga, MD; Jose Luis Morero, DM; Hugo Neffen, MD; Santiago Rossi, MD; Eduardo Schiavi, MD Hospital Maria Ferrer, Buenos Aires, Argentina Chest. 2013;144(4_MeetingAbstracts):82A. doi:10.1378/chest.1698995
Abstract SESSION TITLE: Asthma Posters SESSION TYPE: Original Investigation Poster PRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PM PURPOSE: The aim of this study was to compare the levels of IL-8 and IL17-A in sputum samples from patients admitted for an asthma exacerbation classified in two different categories based on WHO criteria: a) Difficult to treat severe asthma (DTTSA) due to non-adherence or accessibility issues and b) Treatment resistant severe asthma (TRSA), in order to understand the role of these molecules in the pathogenesis of the diverse presentations of the disease. The third category, Untreated severe asthma was not found between our patients. METHODS: Cross sectional prospective observational study of admissions to a respiratory hospital. DTTSA and TRSA were diagnosed according to WHO criteria; FeNO and spirometry were first measured, followed by assisted sputum. Samples were processed with dithiotreitol, cytospined and stained. Supernatants were stored at -80°C. IL-8 and IL17-A were measured by ELISA. Data were expressed as the mean ± SEM and were analyzed using a non-parametric Mann Whitney test. RESULTS: We recruited 12 patients with TRSA (9 of them never smoked and 2 were pastsmokers); and 38 with DTTSA (24 of them never smoked, 6 were past-smokers and 7 were active smokers). No significant differences were found between initial FEV1or FeNO between both groups: 775.5±86.L/S and 37.7±10.8 ppb in TRSA vs 911.4±60.4 L/S and 39.4±5.2 ppb in DTTSA patients. A significant increase of neutrophils in sputum samples from patients with TRSA vs DTTSA (32.5±7.5% vs 14.8±2.0%, p<0.05) was found. Moreover, 25% of TRSA but only 2.6% of DTTSA were neutrophilics. Sputum levels of IL-8 were higher in TRSA compared
with DTTSA patients (724.8±47.1pg/ml vs 419.5±80.1pg/ml, p<0.05). No differences were found when the levels of IL17-A were analyzed (13.6±4.6pg/ml vs 14.1±3.3pg/ml respectively). CONCLUSIONS: Consistent with previous data, we did not find differences in FeNO and FEV1 between TRSA and DTTSA patients. A significant increase of IL-8, but not IL-17A, was found in the sputum of TRSA vs DTTSA patients. CLINICAL IMPLICATIONS: This work contributes to understand the role of IL-8 in the pathogenesis of TRSA. DISCLOSURE: The following authors have nothing to disclose: Glenda Ernst, Auteri Santiago, Fabian Caro, Daniel Colodenco, Ricardo Del Olmo, Martin Fernandez, Jorge Geffner, Dora Lombardi, Guillermo Menga, Jose Luis Morero, Hugo Neffen, Santiago Rossi, Eduardo Schiavi No Product/Research Disclosure Information