Chronic obstructive pulmonary disease (COPD) is characterised by chronic inflammation of the respiratory tract. Thus, Th1/Th2 cytokines could be a useful tool to monitor exacerbations of COPD. The aim of the present study was to investigate Th1 and Th2 cytokines in exhaled breath condensate (EBC) of exacerbated COPD patients.
The study population consisted of 20 patients with exacerbated COPD. The inclusion criteria were as follows: FEV1/vital capacity <70%, FEV1 <80% predicted value and stage 3 or 4 of GOLD. EBC samples were collected within 24 hours after admittance to hospital and three months later. Cytokines were measured simultaneously in a single EBC sample of exacerbated COPD patients by using a Human Cytokine kit II BD. This kit allowed us to quantitatively measure IL-2, IL-4, IL-6, IL-10, IFNγ and TNFα protein levels.
The concentration of cytokines in the EBC of patients was close to the detection limits of the assay. The mean concentration of IFNγ, TNFα, IL-10, IL-6, IL-4 and IL-2 at admittance to hospital was 40±5.1, 15±0.5, 23±1.0, 24±0.6, 34±1.1 and 15±0.4 respectively; while the concentration at three months after admittance was 39±2.5, 18±1.7, 27±1.6, 30±3.3, 44±6.2; 20±2.7 respectively. Although the parameters did not change significantly two months after admittance, there was a tendency to increase the concentration of IL-10(p<0.06) and IL-2(p<0.08). Remarkably, by analyzing mainly IFNγ and IL-4, two clearly differentiated groups of patients appeared: those whose EBC concentration of cytokines had increased (Figure A) and those whose EBC concentration of cytokines had decreased (Figure B) two months after admittance.
Considering the sample population as a whole, this study showed no significant changes in cytokine concentration in EBC three months after admittance to hospital. However, two different groups of patients could be identified based on the pattern of cytokine.
Perhaps the presence of two group of patients may correlate with outcome of patients and will define a new perspective in the treatment of these patients.
Juan Mazzei, None.