Objective To investigate the clinical significance of anaphylatoxin C3 a in induced sputum in patients with asthma.Methods The patients with acute exacerbation of asthma treated at our department between September, 2006 and February,2007 were included in the study. The demographic data, medical history, levels of lung function and C3 a levels in induced sputum were assessed. Results A total of 33 patients were included in the study. The level of C3 a in induced sputum was significantly higher in patients wi...