[Detection of metallo-beta-lactamases in gram-negative bacilli isolated in hospitals from Romania--research fellowship report].

Abstract

The emergence of carbapenem resistance in Gram-negative bacilli has become a global concern since these beta-lactams are often the only effective treatment left against many multiresistant strains. Metallo-beta-lactamase-producing isolates are now widespread worldwide, and especially in Europe where they have been responsible for rather large outbreaks. Our study proposes to investigate the presence of such isolates in Romania and to characterize them at the molecular level. A total of 28 clinical isolates clinical isolates of Pseudomonas aeruginosa and Acinetobacter baumannii were collected between 2003 and 2007 from 5 hospitals in 3 cities in north-east of Romania (Iaşi, Bacău, Galaţi). Antimicrobial susceptibility testing was performed according to CLSI guidelines. MBL detection was performed using the EPI phenotypic test and PCR, that was confirmed by hydrolysis test. The structure of MBL-encoding class 1 integron was determined by PCR mapping and sequencing. Genotyping was performed by RAPD. Only 2 strains showed a positive EPI test. PCR and sequencing revealed the presence of bla(VIM-2) and bla(IMP-13) genes, in strains 16GL Pa and 247Pa, respectively. RAPD showed clonal relatedness between the Pa247 and an Italian IMP-13 producing strain. Despite the infrequent occurrence of metallo-beta-lactamases in our settings, both VIM- and IMP-types are present in Romanian Pseudomonas aeruginosa clinical isolates.