In vitro Activity of Different Antibacterial Agents in Combination with Each Other against Multidrug-resistant Acinetobacter baumannii.

To the Editor: Acinetobacter baumannii is a major cause of nosocomial infections associated with high morbidity and mortality, primarily in immunocompromised patients in Intensive Care Units. Multidrug-resistant (MDR) and extensively drug resistant (XDR) A. baumannii had become a serious widespread threat to nosocomial infections.[1] There are limited effective antimicrobial agents against these strains. Moreover, the mortality rate of A. baumannii infections was associated with inappropriate antimicrobial treatment.[1,2] It is critical to use effective antimicrobials for treating these A. baumannii infections. Meanwhile, discovering new antimicrobials and useful combinations of approved drugs against these strains is urgent. Thus, in this study, we discussed the in vitro activity of different antibacterial agents, including imipenem (IMI), meropenem (MEM), amikacin (AMK), ciprofloxacin (CIP), cefoperazone/sulbactam (CPS), and sulbactam (SUL) in combination with each other against MDR A. baumannii isolated from different provinces of China.