泛耐药鲍曼不动杆菌1株遗传学特征分析

目的研究1株泛耐药鲍曼不动杆菌的耐药机制及遗传学特征。方法采用K—B法测定临床分离的鲍曼不动杆菌对15种抗菌药物的敏感性，筛选出1株泛耐药株，用PCR法对相关耐药基因进行检测，包括对15种超广谱β-内酰胺酶基因、3种金属β-内酰胺酶基因、2种AmpC酶基因、7种氨基糖苷类修饰酶基因、I类整合子及转座子遗传标志物。结果该株鲍曼不动杆菌除对头孢哌N／舒巴坦表现为中度敏感外，对其余14种抗菌药物皆表现为耐药；t3-内酰胺酶基因TEM、OXA-23群、染色体AmpC酶（ADC）基因阳性，氨基糖苷类修饰酶基因aac（3）-I、aac（6’）-Ib、ant（3”）-I阳性、I类整合子qacE△1-sull、转座子tnpU基因扩增阳性。该株AmpC酶（ADC酶）DNA序列为新亚型。结论鲍曼不动杆菌耐药严重，存在多种耐药机制，临床上需引起重视。

The genetic feature of a strain of pan-drug resistant Acinetobacter baumannii

Objective To investigate the genetic features related to drug-resistance of a strain of pan-drug resistant Acinetobacter baumannii. Methods The susceptibilities to 15 antibacterial agents were detected in Acinetobacter baumannii by K-B paper diffusing method. A strain of pan-drug resistant Acinetobacter baumannii was selected. The drug-resistant genes of the selected strain were amplified by polymerase chain reaction （PCR）, including 15 extended-spectrum β-lactamase genes, 3 metal β-lactamase genes, 2 AmpC enzyme genes, 7 aminoglycoside modifying enzyme genes and the genetic markers of integron I and transposons. Results The strain was resistant to 14 antibacterial agents except cefoperazone sodium/ sulbactam. β-lactamases genes （TEM, OXA-23 and ADC）, aminoglycosides modification enzyme genes [aac（3）- I , aac（6＇）- I b and ant（3＂ ）- I ] , integron I qacE△1-sull and transposon tnpU were positive in PCR amplification. A new subtype of AmpC （chromosome） desoxyribonucleic acid （DNA） was detected. Conclusion Acinetobacter baumannii is of high resistance to most antibacterial agents, and the mechanisms of the resistance are complex.