臨床分離大腸埃希菌產(chǎn)ESBLs的基因型及耐藥性研究
發(fā)布時間:2018-06-29 08:04
本文選題:大腸埃希菌 + 超廣譜β-內(nèi)酰胺酶 ; 參考:《中國醫(yī)科大學(xué)》2007年碩士論文
【摘要】: 目的 大腸埃希菌是臨床上常見的致病菌,隨著三代頭孢菌素等廣譜β-內(nèi)酰胺類抗生素在臨床上的廣泛應(yīng)用,產(chǎn)超廣譜β-內(nèi)酰胺酶(ESBLs)大腸埃希菌感染日益增多,這也是細(xì)菌對新一代β-內(nèi)酰胺類抗生素耐藥的主要原因。ESBLs由質(zhì)粒介導(dǎo),易在同種屬甚至不同種屬細(xì)菌間傳遞造成暴發(fā)流行。由于各個國家和地區(qū)使用的抗生素不同,流行的ESBLs基因型各不相同。ESBLs的傳播性以及它們的多重耐藥性給臨床抗感染治療造成了極大困難,,及時準(zhǔn)確檢出ESBLs對防止ESBLs流行、控制醫(yī)院內(nèi)感染和指導(dǎo)臨床治療有著非常重要的意義。為此,本研究以臨床分離的大腸埃希菌為對象,采用NCCLS推薦的確證試驗檢測產(chǎn)ESBLs的菌株,計算ESBLs的分離率,分析其耐藥性,并對ESBLs進(jìn)行基因分型,為臨床治療、預(yù)防產(chǎn)ESBLs細(xì)菌引起的感染提供一定的參考。 方法 將2004年1月至2005年12月間的臨床非重復(fù)菌株共120株,按照美國國家臨床實驗室標(biāo)準(zhǔn)化委員會(NCCLS)推薦的ESBLs表型確證試驗法篩選產(chǎn)ESBLs大腸埃希菌。提取產(chǎn)ESBLs菌的質(zhì)粒DNA,特異性引物擴(kuò)增TEM型、SHV型、CTX-M-1組、CTX-M-9組基因,對所有陽性的PCR產(chǎn)物進(jìn)行DNA測序。 結(jié)果 藥敏結(jié)果顯示本實驗產(chǎn)ESBLs大腸埃希菌表現(xiàn)為多重耐藥性,其中氨芐西林100%,第一、二代頭孢菌素頭孢唑啉、頭孢呋新均在90%以上,第三代頭孢菌素頭孢曲松鈉80%,頭孢噻肟76.7%,其它四環(huán)素90%,左氧氟沙星86.6%,環(huán)丙沙星85%,復(fù)方新諾明83.3%,酶抑制復(fù)合制劑哌拉西林/他唑巴坦3.3%,頭孢哌酮/舒巴坦16.7%,非產(chǎn)ESBLs大腸埃希菌組氨芐西林88%,四環(huán)素80%。產(chǎn)ESBLs菌株與非產(chǎn)ESBLs菌株未發(fā)現(xiàn)對亞胺培南耐藥。 產(chǎn)ESBLs大腸埃希菌基因檢測陽性45株,占75%。其中CTX-M-14占82.2%(37/45)、CTX-M-9占4.4%(2/45)、CTX-M-15占2.2%(1/45)、CTX-M-22占4.4%(2/45)、CTX-M-24占2.2%(1/45)、CTX-M-27占2.2%(1/45)。45株產(chǎn)ESBLs菌中,只有1株菌株檢出兩種基因型共同存在,占2.2%,為CTX-M-14和TEM-1。 討論 本研究結(jié)果表明,產(chǎn)ESBLs的大腸埃希菌對多種抗生素耐藥,但未發(fā)現(xiàn)對亞胺培南耐藥菌株,建議對于重癥感染的治療應(yīng)首選碳青霉烯類抗生素。 產(chǎn)ESBLs大腸埃希菌臨床分離株中以產(chǎn)CTX-M型酶為最常見,其中主要為CTX-M-14。 合理使用抗生素,特別是三代頭孢菌素,加強醫(yī)院高危人群的耐藥監(jiān)測,實行目標(biāo)治療,有利于減少產(chǎn)ESBLs大腸埃希菌耐藥菌株的產(chǎn)生及傳播。 結(jié)論 產(chǎn)ESBLs大腸埃希菌對亞胺培南全部敏感,其他抗生素均有耐藥。中國醫(yī)科大學(xué)附屬第一醫(yī)院產(chǎn)ESBLs大腸埃希菌以CTX-M型酶最常見,主要為CTX-M-14。
[Abstract]:Purpose
Escherichia coli is a common pathogenic bacterium in clinic . With the wide application of the broad - spectrum 尾 - lactam antibiotics such as Cephalosporins in clinic , it is very important to produce extended - spectrum 尾 - lactam antibiotics .
method
A total of 120 clinical non - repetitive strains were screened from January 2004 to December 2005 . The strains of E . coli were isolated from the strains of Escherichia coli . The plasmid DNA was extracted from the producing strains , TEM type , SHV type , CTX - M - 1 group , CTX - M - 9 group , and DNA sequencing was performed on all positive PCR products .
Results
The results showed that the strains of Escherichia coli produced by this experiment showed multiple drug resistance , in which ampicillin was 100 % , the first , the second generation cephalosporin ceftizolin and ceftiofur were all over 90 % , the third generation Cephalosporins sodium 80 % , ceftiofur hydrochloride was 76.7 % , the other tetracyclines were 90 % , levofloxacin 86.6 % , ciprofloxacin 85 % , tetracyclines 80 % , and the non - producing strains were not found to be resistant to Imipenem .
CTX - M - 14 accounted for 82.2 % ( 37 / 45 ) , CTX - M - 9 was 4.4 % ( 2 / 45 ) , CTX - M - 15 was 2.2 % ( 1 / 45 ) , CTX - M - 27 was 2.2 % ( 1 / 45 ) , CTX - M - 27 accounted for 2.2 % ( 1 / 45 ) , CTX - M - 27 was 2.2 % ( 1 / 45 ) .
discuss
The results of this study showed that the strains of E . coli were resistant to various antibiotics , but did not find the resistant strains to Imipenem , suggesting that the treatment of severe infection should be the preferred choice of Carbapenem antibiotics .
CTX - M - type enzyme is the most common in the clinical isolates of Escherichia coli , which is CTX - M - 14 .
The rational use of antibiotics , especially the cephalosporin of the third generation , strengthens the drug resistance monitoring of the high - risk population in the hospital , carries out target treatment , and is beneficial to reduce the generation and spread of the drug - resistant strains of Escherichia coli .
Conclusion
In the first hospital , CTX - M - type enzyme is the most common type of CTX - M - type enzyme , and CTX - M - 14 is the most common .
【學(xué)位授予單位】:中國醫(yī)科大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2007
【分類號】:R378.2
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 張征,劉榮欣,趙小潔,李亞威,孫靜娜;產(chǎn)超廣譜β-內(nèi)酰胺酶大腸埃希菌的藥敏分析[J];河北醫(yī)藥;2005年09期
2 鄧霞林,謝榮愛,趙亞南;140株腸桿菌科細(xì)菌ESBLs檢測及相關(guān)因素分析[J];上海醫(yī)學(xué)檢驗雜志;2003年05期
3 朱德妹,熊自忠,汪復(fù),胡付品,吳n\;超廣譜β-內(nèi)酰胺酶和細(xì)菌耐藥性[J];中華傳染病雜志;2000年03期
4 汪復(fù),吳n
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