Giraud-Morin C, Fosse T
Laboratoire de bactériologie, hôpital de l'Archet, 151, route de Saint-Antoine-de-Ginestière, BP 3079, 06202 Nice cedex 3, France.
Pathol Biol (Paris). 2008 Nov-Dec;56(7-8):417-23. doi: 10.1016/j.patbio.2008.07.003. Epub 2008 Oct 9.
ESBL producing enterobacteria (E-ESBL+) are always a public health concern, mainly due to increase of CTX-M beta-lactamase. So, 542 new strains were isolated in the CHU de Nice during the 2005-2007 period. The aim of this work was to characterize the ESBL and to type isolates suspected to be implicated in outbreaks.
Every first E-ESBL+ was studied, the antibiotype was defined by the agar diffusion technique. Type of ESBL was determined by PCR, followed by sequencing for CTX-M and SHV enzymes. Typing was performed when several strains of one species had same antibiotype and beta-lactamase.
CTX-M type ESBL are predominant (45% of all E-ESBL+), mainly in Escherichia coli (34.5%). The TEM24 ESBL was the second predominant type (34.5%), mainly in Enterobacter aerogenes (18.6%) and Klebsiella pneumoniae (9.4%). SHV5/12 ESBL was found mainly in Enterobacter cloacae (7.5%). Several epidemic situations were identified, with CTX-M15 in Escherichia coli (2005/2006: 27 patients), SHV5/12 in Enterobacter cloacae (2006: 10 patients) and TEM in Proteus mirabilis (2007: nine patients). Enterobacter aerogenes is still endemic (101 patients) while an epidemic clone of TEM24 producing K. pneumoniae persists especially in an intensive care unit (26 patients during the three years).
Caracterization of E-ESBL+ is essential to better understand their mode of dissemination, monitor the emergence of new enzymes and adapt the efforts against BMR cross transmission.
产超广谱β-内酰胺酶（ESBL）的肠杆菌（E-ESBL+）一直是公共卫生关注的问题，主要是由于CTX-Mβ-内酰胺酶的增加。因此，2005年至2007年期间在尼斯大学中心医院分离出542株新菌株。这项工作的目的是对ESBL进行特征分析，并对怀疑与暴发有关的分离株进行分型。
研究每一株首个分离出的E-ESBL+，通过琼脂扩散技术确定抗菌型。通过PCR确定ESBL类型，随后对CTX-M和SHV酶进行测序。当一个物种的几株菌株具有相同的抗菌型和β-内酰胺酶时进行分型。
CTX-M型ESBL占主导（占所有E-ESBL+的45%），主要存在于大肠杆菌中（34.5%）。TEM24 ESBL是第二主导类型（34.5%），主要存在于产气肠杆菌（18.6%）和肺炎克雷伯菌（9.4%）中。SHV5/12 ESBL主要存在于阴沟肠杆菌中（7.5%）。确定了几种流行情况，大肠杆菌中存在CTX-M-15（2005/2006年：27例患者），阴沟肠杆菌中存在SHV5/12（2006年：10例患者），奇异变形杆菌中存在TEM（2007年：9例患者）。产气肠杆菌仍为地方流行（101例患者），而产TEM24的肺炎克雷伯菌流行克隆持续存在，尤其是在重症监护病房（三年间有26例患者）。
对E-ESBL+进行特征分析对于更好地了解其传播方式、监测新酶的出现以及调整针对耐多药交叉传播的措施至关重要。
