In vitro comparison of colistin- versus tigecycline-based combinations against carbapenem resistant Acinetobacter baumannii intensive care unit clinical isolates

Background: Acinetobacter baumannii (A. baumannii) has emerged as a nosocomial pathogen especially in the intensive care units (ICUS). It’s enlisted at top of urgent threat level organisms CDC’s antibiotic resistance threats report. Objectives: To assess prevalence, risk factors health associated infection by A. baumannii, and to compare in-vitro efficacy colistin sulfate- tigecycline combinations versus their individual combination with levofloxacin meropenem against carbapenem resistant clinical isolates from an Egyptian tertiary hospital ICUs. Methodology: The study included 250 ICU patients, samples were collected according site infection. was isolated, identified tested for susceptibility disc diffusion. Broth microdilution method used assessment colistin, Tigecycline, levofloxacin, meropenem. Thirty all carbapenems checkerboard effect combinations. Results: forty-six highest prevalence respiratory secretions. Prior administration failure empirical therapy found be major infections baumannii. Colistin showed synergy (50%). Tigecycline-meropenem had antagonistic (66.7%). Conclusion: No confirmed this study. Only colistin-based combinations, particularly those may confer therapeutic benefits carbapenem-resistant