Аннотация
В настоящей работе представлены данные исследования распространённости и молекулярной эпидемиологии грамотрицательных бактерий, продуцирующих металло-β-лактамазы (МБЛ), в России (в 1998-2010 гг.), Беларуси и Казахстане (в 2005-2010 гг.). Анализ нозокомиальных штаммов, выделенных в рамках нескольких многоцентровых эпидемиологических исследований в России, выявил стремительное нарастание доли МБЛ-положительных изолятов Pseudomonas aeruginosa (от 4,5 до 20,3% в период между 2002-2004 и 2006-2007 гг.), которое в основном было связано с эпидемическим распространением клона P. aeruginosa ST235 VIM-2. Циркуляция данного клона отмечена не только на всей территории России, но и в нескольких городах Беларуси и Казахстана. Доля ST235 среди всех исследованных МБЛ-продуцирующих изолятов P. aeruginosa (n=711) составила 96,3%, остальные изоляты относились к неродственным сиквенс-типам: ST234 (3,4%), ST244 (0,1%) и ST270 (0,1%). Большинство изолятов были чувствительны только к полимиксинам. У P. aeruginosa гены МБЛ — VIM-2 (99,6%) и нового варианта IMP-1 (Glu59/Lys) — IMP-30 (0,4%), найдены в составе интегронов пяти различных типов. В двух случаях установлен вероятный перенос гена blaVIM-2 в составе наиболее распространённого Tn5090-ассоциированного интегрона от ST235 к ST234 и ST244. Помимо P. aeruginosa, продукция МБЛ (VIM-4) выявлена у единственного штамма Escherichia coli.
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