Abbassi M-S, Touati A, Achour W, Cherif A, Jabnoun S, Khrouf N, Ben Hassen A
Laboratory of the National Bone Marrow Transplantation Centre, Street Djebel-Lakdhar, Bab-Saadoun, 1006 Tunis, Tunisia.
Pathol Biol (Paris). 2009 Jul;57(5):363-7. doi: 10.1016/j.patbio.2007.09.018. Epub 2008 Jan 4.
The aim of this study was to investigate the molecular epidemiology of Stenotrophomonas maltophilia strains responsible for respiratory infection in a neonatal intensive care unit (NICU) in Tunis City, isolated during 22 months (December 2003-September 2005).
Twelve strains of S. maltophilia isolated from tracheal aspirates of distinct infants and two environmental strains were tested for antibiotic susceptibility and genotyped by pulsed-field gel electrophoresis (PFGE) method.
Unlike a large heterogeneity demonstrated by the antibiotyping method, PFGE identified two concomitant outbreaks consisting of nine, including an environmental strain (clone A), and four strains (clone B), respectively; a distinguishable strain was classified in a unique pattern (PFGE type C). The long-term dissemination of these strains is a characteristic feature of these outbreaks. Improvement of hygienic conditions attributed to a markedly decrease in their isolation frequencies. Concomitant outbreaks and long period persistence of S. maltophilia in NICU is an important finding of this study.
Identification of two clonal strains of S. maltophilia responsible of respiratory infection. Epidemic strains are hardly eradicated when colonization is established.
本研究旨在调查2003年12月至2005年9月期间在突尼斯市一家新生儿重症监护病房（NICU）分离出的嗜麦芽窄食单胞菌菌株导致呼吸道感染的分子流行病学情况。
对从不同婴儿气管吸出物中分离出的12株嗜麦芽窄食单胞菌菌株以及2株环境菌株进行抗生素敏感性测试，并采用脉冲场凝胶电泳（PFGE）方法进行基因分型。
与抗菌谱分型方法显示的高度异质性不同，PFGE鉴定出两起同时发生的暴发，分别由9株（包括1株环境菌株，克隆A）和4株（克隆B）组成；1株可区分的菌株被归类为独特模式（PFGE型C）。这些菌株的长期传播是这些暴发的一个特征。卫生条件的改善导致其分离频率显著下降。NICU中嗜麦芽窄食单胞菌的同时暴发和长期持续存在是本研究的一项重要发现。
鉴定出两株导致呼吸道感染的嗜麦芽窄食单胞菌克隆菌株。当定植建立后，流行菌株很难根除。
