Strains of Klebsiella pneumoniae Producing Extended Spectrum Beta-Lactamases, Isolated from Organ Recipients

Abstract

Objective The aims of this work were to define the effectiveness of identification of the extended-spectrum beta-lactamases (ESBL) phenotype, and to define the genotype of Klebsiella pneumoniae β-lactamase. Materials and Methods We identified ESBL phenotypes in 110 strains of K pneumoniae isolated from samples from patients of transplantation wards, using the double-disk synergy test (DDST). For the chosen strains, polymerase chain reaction (PCR) was applied to detect genes determining SHV, CTX-M, and TEM. Results We showed synergism of clavulanic acid and investigated antibiotics including ceftazidime (89.1%), cefotaxime (80%), and aztreonam (82.7%) against ESBL-positive strains PCR revealed that TEM and CTX-M were present in 88.89% of strains. Conclusions The ESBL mechanism of resistance is frequent among K pneumoniae strains isolated from transplant recipients. Strains with simultaneous synthesis of more than one beta-lactamase predominated.