In Vitro Susceptibility of Tigecycline and Colistin Against Stenotrophomonas maltophilia

Abstract

Introduction: Gram-negative bacillus Stenotrophomonas maltophilia is resistant to drugs (multi-drug resistance-MDR) and it can be isolated from nature. Treatment of the infections resulting from S. maltophilia could be problematic due to multi-resistance.

Materials and Methods: 72 S. maltophilia strains isolated from clinical samples were included into the study. Sensitivity was determined using Tigecycline and Colistin E-test MIC method performed in the Clinical Microbiology laboratory of Baskent University, Medical Faculty between 2010 and 2014.

Results: In our study, colistin MIC range was found as 0.016-8 mg/L. MIC50 and MIC90 values were determined respectively as 1.5 mg/L and 12 mg/L. Tigecycline MIC range was 0-96 mg/L, and MIC50 was 0.19 mg/L and MIC90 was 1.5 mg/L. Furthermore, one tigecycline resistant strain was detected.

Conclusion: We believe that the determination of novel treatments and protocols and their standardization using multidisciplinary approaches can facilitate to cope with problematic and resistant nosocomial infections developed by S. maltophilia.