Molecular epidemiology of SPM-1-producing Pseudomonas aeruginosa by rep-PCR in hospitals in Parana, Brazil

BackgroundInfections caused by multidrug resistant microorganisms are a global health problem, and Pseudomonas aeruginosa is an important nosocomial pathogen, easily disseminated in the hospital environment. The aim of this study was to determine SPM-1 in P. aeruginosa strains in 30 Brazilian hospitals and the genetic similarity of isolates.MethodsWe analyzed 161 isolates of carbapenem-resistant P. aeruginosa. Imipenem/EDTA and imipenem strip were used for phenotypic detection of MBL production; and real-time polymerase chain reaction (PCR) for genetic detection. Genetic similarity was determined by rep-PCR.ResultsWe obtained 136/161 (84.5%) isolates with positive phenotypic result for metallo-β-lactamase (MBL) and the blaSPM-1 gene was identified in 41 isolates. There was a predominant profile (> 95% of genetic similarity) in 92.7% of isolates. This predominant profile was widely disseminated in Paraná state.ConclusionSPM-1 is the main MBL identified in carbapenem-resistant P. aeruginosa in Southern Brazil. The genetic similarity among some isolates suggests a clonal expansion.