Zidovudine enhances activity of carbapenems against NDM-1-producing Enterobacteriaceae

Objectives: To investigate the efficacy of zidovudine in combination with carbapenems against NDM-1-producing Enterobacteriaceae.

Methods: MICs were determined using the broth microdilution method. The combinatory effects of zidovudine and carbapenems were examined using the chequerboard method and time-kill analysis.

Results: We found that the NDM-1-producing strains were resistant to all carbapenems tested. FIC index from chequerboard assay demonstrated that zidovudine synergized with carbapenems against all the NDM-1 strains. Time-kill analysis demonstrated significant synergistic activity when a low level of zidovudine was combined with meropenem.

Conclusions: Zidovudine in combination with carbapenems produced synergistic activity against NDM-1 Enterobacteriaceae strains in vitro.