Outbreak caused by a multidrug-resistant Klebsiella pneumoniae clone carrying blaVIM-12 in a university hospital.

From November 2006 to April 2007, nine nonrepetitive isolates of Klebsiella pneumoniae with reduced susceptibility or resistance to carbapenems were recovered from clinical specimens from separate patients hospitalized in a tertiary care hospital. The imipenem-EDTA synergy test was positive for all isolates. PCR, sequencing, and transferability experiments revealed the novel bla(VIM-12) metallo-beta-lactamase gene, which was plasmid mediated and located in a class 1 integron.

Outbreaks in distinct regions due to a single Klebsiella pneumoniae clone carrying a bla VIM-1 metallo-{beta}-lactamase gene.

From December 2004 to March 2005, 27 Klebsiella pneumoniae clinical isolates that were positive by the imipenem-EDTA double-disk synergy test and that exhibited a single macro-restriction pattern were recovered in two distinct Greek hospitals. The isolates carried a transferable bla(VIM-1) metallo-beta-lactamase gene in a class 1 integron. Reverse transcriptase PCR showed that the gene was similarly expressed in low- and high-level carbapenem-resistant isolates, indicating the existence of additional resistance mechanisms.