Detection of carbapenemase-producing bacteria in a public healthcare center from Venezuela

The dramatic increase in the prevalence and clinical impact of infections caused by Carbapenemase-Producing Bacteria in the nosocomial setting in Latin America represents an emerging challenge to public health. The present study detected carbapenemase-producing Gram-negative bacteria in patients from a Hospital from Venezuela, by phenotypic and genotypic methods.

The bacterial identification was carried out using conventional methods. The resistance to carbapenems was performed by Kirby-Baüer disk diffusion method, according to CLSI recommendations. The modified Hodge Test, double-disk with phenylboronic acid, double-disk with EDTA and Blue Carba Test were performed to detect phenotypic carbapenemase producers. The carbapenemase-encoding genes blaKPC, blaVIM, blaIMP, blaOXA-2, blaOXA-3, blaOXA-15 and blaOXA-21 were determined.

The bacterial species identified were Klebsiella pneumoniae complex (181), Pseudomonas aeruginosa (51), and Acinetobacter baumannii-calcoaceticus complex (119). KPC-type was detected in 40.17% of isolates and VIM-type in 14.53%. KPC-type gene was only identified in K. pneumoniae isolates (77.9%). VIM-type gene was identified in P. aeruginosa (86.27%) and K. pneumoniae isolates (3.87%). There was not detection of IMP-type and OXA-type genes.

We found a predominance of K. pneumoniae KPC producers and a high rate of VIM-producing P. aeruginosa. The epidemiology of CPB in Venezuela is rapidly evolving, and enhanced surveillance and reporting are needed across the healthcare continuum.