Abstract: Objective To investigate the distribution of NDM-1 in Acinetobacter spp. Methods Twenty-five isolates of Acinetobacter baumannii and 3 isolates of A. lwoffii and 2 isolates of A.junnii that were resistant to imipenem were selected for the study. Carbapenemases were screened by modified Hodge test and EDTA disk synergy test. The genotypes of carbapenamases were determined by PCR and DNA sequencing. Plasmid conjugation was performed to study the transfer of carbapenem resistance. Strain homology was analyzed by PFGE. Results Ten out of 25 A. baumannii strains were positive for MHT but all were negative for EDTA disk synergy test,and all the 25 strains were positive with OXA-23-like but negative for NDM-1. All the non-A.baumannii isolates were positive for EDTA disk synergy test but negative for MHT. The strains were just positive for NDM-1 detected by PCRs and negative for the other carbapenamases. The NDM-1 positive strains had different PFGE profiles. PFGE showed high homology for A.baumannii with mainly A clone. Conclusions NDM-1 was distributed in the bacterias rather than A. baumannii,which were resistant to imipenem and the positive isolates had different PFGE profiles.

Key words: NDM-1, Acinetobacter, Homology