Abstract:

Objective To investigate the risk factors,clinical characteristics,isolation rate and drug resistance of Stenotrophomonas maltophilia infection,and to provide a reference for its clinical prevention and treatment. Methods A total of 313 isolates of Stenotrophomonas maltophilia were collected from January 2012 to December 2016,and their data and antibiotic susceptibility results were analyzed retrospectively. Results The 313 isolates of Stenotrophomonas maltophilia were collected from 260 cases of respiratory tract infection and 53 cases of non-respiratory tract infection,and the major distribution was in Department of Respiratory. The high risk factors were old age,usage of antibiotics for long time,primary pulmonary and so on. The isolation rates of Stenotrophomonas maltophilia isolated from 2012 to 2016 in Gram-negative bacilli were 5.3%（97/1 831）,3.2%（59/1 818）,3.7%（60/1 616）,2.3%（51/2 212） and 1.5%（46/3 028）（P<0.05）. The drug resistance rates of 313 isolates of Stenotrophomonas maltophilia against sulfamethoxazole-trimethoprim,levofloxacin,minocycline,ceftazidime,ticarcillin-clavulanic acid and chloramphenicol were 29.6%,20.4%,3.8%,68.9%,44.4% and 20.9%. The drug resistance rate to ceftazidime was increased,and the drug resistance rates to the other drugs were decreased year by year（P<0.001）. The drug resistance to ceftazidime,minocycline and chloramphenicol in isolates from respiratory tract samples had statistical significance compared with those from non-respiratory tract samples（P<0.05）. Conclusions The risk factors of Stenotrophomonas maltophilia infection are old age,primary pulmonary,usage of antibiotics,tracheotomy,intensive care unit admission and so on. Rational antibiotic use is important. Stenotrophomonas maltophilia infection should be treated with minocycline combined with other antibiotics.

Key words: Stenotrophomonas maltophilia, Drug resistance, Distribution, Clinical characteristic, Risk factor