In recent studies on the evaluation of airway and systemic inflammation in patients with asthma, various biomarkers have been measured in exhaled breath condensate (EBC), like nitric oxide, nitrates/nitrites and 8-isoprostane. Similarly, measurement of biomarkers in blood, notably high-sensitivity c-reactive protein (hs-CRP), 8-isoprostane and antioxidants (catalase, superoxide dismutase, glutathione peroxidase, glutathione), has also been used to reflect the levels of systemic inflammation and oxidative stress.