多重PCR技术在检测鲍曼不动杆菌β-内酰胺酶基因中的应用

The Use of Multiple PCR in the Detection of Acinetobacter baumannii β-lactamase Genes

目的建立快速、高效检测鲍曼不动杆菌（AB）β-内酰胺酶基因的方法，探讨β-内酰胺酶基因与多药耐药性（MDR）的关系。方法琼脂稀释法检测90株AB对20种常用β-内酰胺类抗菌剂的最低抑菌浓度；多重PCR（M—PCR）技术检测5种常见β-内酰胺酶基N。结果90株AB对头孢唑啉、氨曲南、头孢噻吩、头孢西丁、氯唑西林、氨苄西林、头孢哌酮的耐药率高达82．8％～94．2％。64．4％的AB检出β-内酰胺酶基因，其中PER-150．0％、AmpC45．8％、TEM-135．1％、SHV-522．4％、CTX-M26．8％。结论p内酰胺酶基因在AB中具有较高的检出率，与其MDR密切相关；所构建M—PCR检测体系能同时扩增多个陆内酰胺酶基因，是检测耐药基因快速有效的方法。

Objective To establish a rapid and simple method for detection of β-lactamase genes and to investigate the associa- tion of β-lactamase genes with multi-drug resistance in Acinetobacter baurnannii clinical isolates. Methods 90 non-duplicate clinical isolates of Acinetobacter baumannii were collected from the teaching hospital of North Sichuan Medical College. Sensitivity of the 90 clinical strains was detected to 20 kinds of commonly used β-lactam antimicrohial drug. The distribution of five types of β-lactamase genes in these bacteria was analyzed by using multiple PCR. Results The resistant rates of 90 strains of Acinetobacter baumannii were 82.8 % -- 94.2 % to cefazolin, aztreonam, eephalothin, cefoxitin, chlorine cloxacillin, ampicillin and cefoperazone. The multiple PCR results revealed that 64.4 % Acinetobacter baumannii isolates contained one to four kinds of β-lactamase gene,.including genes for PER-1 （50.0%） ,AmpC（45.8%） ,TEM-1（35.1%） ,SHV 5（22.4%） ,and CTX-M2（6.8%）. For most antibacterials tested,the resistant rates of β-lactamase gene-positive strains were higher than the negative strains. The incidence of multidrug resistant isolates in β-lactamase gene-positive strains was much higher than those of negative strains. Conclusion High incidence of β-lactamase genes was found in Acinetobacter baumannii isolates and close association existed between β-lactamase genes and multiple drug resistance. The multiple PCR system can simultaneously amplify different types of β-lactamase genes, which provides a method for rapid detecting of resistance genes in acinetobacter baumannii.