Abstract: Objective To investigate the incidence and bacterial etiology of stent associated respiratory tract infection (SARTI) caused by two types of airway stents. Methods Silicone and coated metal airway stent were placed for patients with central airway stenosis caused by varied pathologies. The incidence of stent related respiratory tract infection, bacteria etiology of SARTI and improved dyspnea score were compared between two groups receiving different airway stent. Results 1) Totally 171 patients received airway stents, and among them, 39 patients (22.81%) developed SARTI. 2) The incidence of SARTI in metal stent group and silicone stent group was 29.21% (26/89) vs. 15.85% (13/82), P<0.05; 3) Bacterial spectrum of SARTI was different in metal and silicone stent groups: staphylococcus aureuswas 38.46% vs. 69.23%, respectively; candida albicans was 23.08% vs. 0%, respectively; Singular proteus was 7.26% vs. 0%, respectively; 4) The narrowed lumen was improved from 74.27%±7.13% to 17.64%±6.22% in the metal stent group, while the data was improved from 74.94%±9.18% to 12.68%±8.32% in the silicone stent group (P<0.01). Accordingly, the dyspnea symptomscore was improvedfrom 2.85±0.89 to 0.85±0.68 in metal stent group, and from 2.88±0.91 to 0±0.61 in the silicone stent group (P<0.05). Conclusions Compared with metal airway stents, silicone stents had a lower incidence of SARTI, which mightbe due to the projections in the silicon stent surface and wider expanded in the bronchial stenosis.

Key words: stent associated respiratory tract infection (SARTI), silicone stent, metal stent, airway stenosis