产ESBLs肺炎克雷伯菌临床菌株耐药性及基因型分析

Analysis of drug resistance and gene types of extended-spectrum β-lactamase-producing Klebsiella pneumoniae isolates

目的研究绍兴地区产超广谱β-内酰胺酶（ESBLs）肺炎克雷伯菌的耐药性及基因型分布。方法分别采用双纸片协同试验和药物敏感试验检测了213株肺炎克雷伯菌产ESBLs率和14种抗菌药物的耐药性。应用PCR检测产酶株的TEM、SHV及CTX—M基因。结果所有菌株对亚胺培南全部敏感，对其余13种抗菌药物耐药率在5．6％-95．3％。ESBLs检出率为45．1％，产ESBLs株对亚胺培南、阿米卡星、哌拉西林／他唑巴坦、左氧氟沙星和阿莫西林／克拉维酸耐药率较低，产ESBLs株对头孢呋辛、头孢曲松、头孢他啶和头孢噻肟耐药率高达80％以上。86．5％产ESBLs肺炎克雷伯菌检测到TEM、SHV和／或CTX—M钝化酶编码基因，其检出率分别为55．2％、60．4％和42．7％。结论本地区以SHV型ESBLs多见，产ESBLs株耐药率远较不产ESBLs菌严重，应加强对肺炎克雷伯菌ESBLs监测，有效控制产ESBLs肺炎克雷伯菌的散播以及耐药基因的传播。

Objective To study the genotype and drug resistance of extended spectrum β - lactamases （ESBLs） - producing K. pneumoniae isolates from Shaoxing area. Methods The ESBLs positive rate and drug resistance to 14 antibiotics of 213 K. pneumoniae isolates were detected by double disk synergy test and drug susceptibility test, respectively. TEM, SHV and CTX - M genes in these isolates were detected by PCR. Results All of the K. pneumoniae isolates were susceptible to imipenem, while the drug resistant rates to the other 13 kinds of antibiotics were between 5.6% -95.3%. The detection rate of ESBLs - producing K. pneumoniae was 45.1% （96/213）. ESBLs -producing isolates were more sensitive to imipenem, amikacin, pip- eracilhn/tazobacta, levofioxacin and amoxicillin/clavulanic acid, while the resistance rates of these isolates to cefuroxime, ceftriaxone, ceftazidime and cefotaxime were all above 80%. In 96 ESBLs - producing isolates, β - lactamases genes was found at least in 83 isolates by PCR, the positive rates of TEM, SHV and CTX - M genes were 55.2% , 60.4% and 42.7% , respec- tively. Conclusion SHV is the most common genotypes of ESBLs in Shaoxing area. The resistance rates of ESBLs - producing K. pneumoniae is higher than that of non ESBLs - producing isolates. Drug resistance surveillance should be strengthened on K. pneumoniae producing ESBLs to effectively control the prevalence of ESBLs - producing K. pneumoniae and the drug resistance genes.