Abstract

Worldwide scientific data show that there is an increasing level of resistance to carbapenems among Enterobacteriaceae rods. We examined the genetic similarity and antimicrobial susceptibility of four KPC-2-positive Klebsiella pneumoniae (with genebla_KPC) which were isolated (for the first time) in two University Hospitals in northeastern Poland. Isolates were obtained from March 2011 to May 2011. The minimum inhibitory concentrations (MICs) of thirteen antibiotics were determined for each isolate. Three of K. pneumoniae isolates (USK1/1, USK2/1 and USK4/1) were intermediate to imipenem (MICs 4 mg/L), and only one isolate (DSK1/1) was resistant to imipenem (MIC >32 mg/L). In addition they were intermediate or susceptible to meropenem (MICs 1-8 mg/L) and doripenem (MICs 2-4 mg/L). Genotyping and dendrogram analysis of four KPC-producing isolates were performed using the repetitive sequence-based polymerase chain reaction (rep-PCR) in the DiversiLab^TM Microbial Typing System. Two rep-PCR clusters (A and B) were determined in University Hospitals in the same city (Bialystok, Poland). Among KPC-2-producing isolates, three isolates (USK1/1, USK2/1, USK4/1) with a similarity of >98% belonged to cluster A, and one (DSK1/1) was dissimilar (<95%) to all the other isolates.

Key words: Klebsiella pneumoniae, KPC-2, genetic similarity, antimicrobial susceptibility, northeastern Poland.