Acinetobacter baumannii multidrug-resistant strain occurrence in liver recipients with reference to other high-risk groups.

INTRODUCTION

The increasing clinical significance of Acinetobacter baumannii species is due to its ability to survive in hospital environments, its species-specific multidrug resistance, and its ability to instantly develop various drug-resistance mechanisms through antibiotic pressure.

MATERIALS AND METHODS

We identified 16 A baumannii strains isolated from patients presenting postoperative infections in 2010. A baumannii isolates were obtained from clinical specimens by standard microbiologic methods. As previously described, we performed polymerase chain reaction (PCR) analysis for carbapenemase-encoding genes (VIM, IMP, SPM, OXA23, OXA24, OXA51, OXA58) in Acinetobacter spp.

RESULTS

The double-disk synergy test phenotypic method did not detect any A baumannii strains producing metallo-beta-lactamaus cultured from swabs from all the patient groups. No products of PCR amplification with specific starters for VIM, IMP, and SPM (Sao Paulo metallo-β-lactamase) genes were found. All analyzed strains were colistin-sensitive. Among five strains from liver recipients, one was imipenem- and meropenem-resistant. Four among six strains isolated from cancer patients were resistant to imipenem and/or meropenem; 1/5 were imipenem-and meropenem-resistant; 1, meropenem-resistant and imipenem-sensitive; 1, meropenem- and imipenem-resistant; and 1 with intermediate resistance to both meropenem and imipenem among swabs cultured from patients with postoperative complication after bone fracture. Fifteen among 16 analyzed A baumannii strains had an OXA51 gene. Two among five A baumannii strains isolated in liver recipients had only an OXA51 gene; one, OXA51 and OXA24 genes; one, OXA51 and OXA23 genes.