A total of 241 isolates of Enterobacter cloacae were collected from the Affiliated Hospital of Shaoyang Medical College, the People's Hospital of Xinning County, the People's Hospital of Wugang and the People's Hospital of Shaoyang County from August 2012 to May 2014, and were identified by API20E. The drug sensitivity test in vitro was performed by K-B method. The armA, npmA, rmtA, rmtB, rmtC and rmtD genes were determined by polymerase chain reaction (PCR). The relation between drug resistant gene and resistant phenotypes was analyzed.

In the 241 isolates of Enterobacter cloacae, 200 isolotes of them were resistant to aminoglycoside antibiotics, including 41.9% isolates being resistant to amikacin, 68.5% to gentamicin, 70.1% to tobramycin, and 63.5% to netilmicin. Two kinds of 16S rRNA methylase genes were detected, among which were armA (96 isolates, 39.8%) and rmtB (17 isolates, 7.1%), and no npmA, rmtA, rmtC and rmtD genes were detected.

16S rRNA methylase is closely related with the drug resistance of aminoglycoside antibiotics. Genotypes carried by 16S rRNA methylases are somewhat different in bacterial isolates from different areas, and armA is a main kind of 16S rRNA methylase gene in Shaoyang.