Distribution and drug resistance of 1702 strains of Stenotrophomonas maltophilia

Objective To understand the distribution characteristics and the change in drug resistance of Stenotrophomonas maltophilia in the past 9 years and provide reference for the clinical treatment. Methods The retrospective analysis was conducted on the isolation rate of Stenotrophomonas maltophilia; the infection distribution and the drug resistance of isolated strains in our hospital from 2002 to 2010. Results A total of 1702 strains of Stenotrophomonas maltophilia were isolated during this period, the isolation rate was 6.9%. The main clinical specimens were sputum, accounting for 92.1%. Stenotrophomonas maltophilia infection were mainly detected in ICU wards (38.8%), neurosurgery department (31.1%) and pneumology department (18.4%). The result of drug susceptibility test showed that the resistance rates of Stenotrophomonas maltophilia to compound ampicillin, imipenem, tobramycin and gentamicin were 100%. The resistance rate of Stenotrophomonas maltophilia was 99.5% to ticarcillin, 99.8% to piperacillin, 99.2% to piperacillin/tazobactam, 95.2% to cefepime, 96.1% to meropenem, 99.6% to amikacin, 78.6% to polymyxin, 60.8% to ciprofloxacin, 43.4% to ticarcillin/clavulanic, 42.2% to ceftazidime and 24.4% to levofloxacin, but the isolated strains of Stenotrophomonas maltophilia were highly sensitive to cefoperazone/sulbactam, compound sulfamethoxazole and minocycline. Conclusion The isolation rate of Stenotrophomonas maltophilia was in increase. Stenotrophomonas maltophilia mainly caused respiratory tract infection and showed serous drug resistance to many kinds of antibiotics. It is necessary for hospitals to monitor its drug resistance, choose antibiotics reasonably and strengthen control of hospital infection to prevent the spread of multidrug-resistant Stenotrophomonas maltophilia.