下呼吸道标本多药耐药鲍氏不动杆菌整合子的检测

Integron Detection in Clinical Multi-resistant Acinetobacter baumannii from Lower Respiratory Tract Specimens

目的研究临床下呼吸道标本分离多药耐药鲍氏不动杆菌中整合子的分布与分型,分析整合子在细菌多药耐药中的作用。方法标准纸片扩散法(K-B)检测耐药性,PCR方法扩增整合酶基因,经电泳后检测扩增产物,2χ检验进行统计学分析。结果在分离出的408株细菌中,共有76株检出整合子,总体检出率为18.6%,其中Ⅰ类整合子检出率为16.9%,Ⅱ类整合子检出率为1.7%;整合子阳性株对多种抗菌药物的耐药率明显高于整合子阴性株,亚胺培南、美罗培南对所有菌株敏感。结论整合子对细菌多药耐药性的产生和传播起着重要作用,应加强临床细菌基因水平的耐药监测,采取有效措施防止耐药性的传播。

OBJECTIVE To investigate the occurrence and distribution of integron among Acinetobacter baumannii isolates from lower respiratory tract specimens and evaluate the integrons to the multi-drug resistantce. METHODS Drug resistance was detected by Kirby-Bauer test. The presence of integron gene was determined by polymerase chain reaction （PCR）with integron specific primer and examined by electrophoresis. Statistic significance for comparison of proportions was calculated by the chi-square test. RESULTS Seventy-six of 408 isolates were identified as being positive for integron gene, positive rate was 18.6 %. The incidences in integron Ⅰ and Ⅱ genes were 16.9% and 1.7%, respectively. The resistance rate to 14 antibiotics in the group with integron was higher than that in the group without it （P〈0. 05）. However, imipenem and meropenem showed good antimicrobial activity among all the strains. CONCLUSIONS Integron harboring multi-drug resistance has been identified among A. baumannii strains. Integron has taken the important part in multi-drug resistance. The results stressed the need for surveillance of the integron content of nosocomial Enterobacteriaceae strains which may be critical to predict and prevent the spread of multi-drug resistant determinants.