Risk factors for development of vancomycin resistant Enterococcus spp. infection

Abstract

Enterococcus faecalis is the most common cause of enterococcal infections, but E. faecium is intrinsically more resistant to antibiotics (1, 2). E. faecalis and E. faecium are oportunistic pathogens that are commonly recovered from patients with significantly compromised host defences and serious co-morbidities, who have received multiple courses of antibiotics and have been hospitalized for prolonged periods (2, 3). An increased risk of vancomycin-resistant Enterococcus (VRE) colonization occurs with immunosupression, hematologic malignancies, organ transplantation, increased intensive care unit or hospital stay, infection of an additional body site (4, 5). In our study we analyzed data of 49 patients with E. faecium or E. faecalis infection, 23 of which were resistant to vancomycin. 21 VRE strains had vanA resistance gene, 2 - vanB gene. Resistance to vancomycin varied depending on the origin of the source of infection. 69.2% (n=18) of vancomycin sensitive Enterococci (VSE) were isolated from abdominal cavity (P<0.001) and 34.8% (n=8) of VRE strains were isolated from urine (P=0.001). E. faecium were more resistant to tested antibiotics in comparison with E. faecalis strains. 71.8% (n=28) of E. faecium and 10% (n=1) of E. faecalis strains were resistant to ampicilin (P<0.001), 56.4% (n=22) of E. faecium and 10% (n=1) of E. faecalis strains were resistant to vancomycin (P<0.009), 51.3% (n=20) of E. faecium and 10% (n=1) of E. faecalis strains were resistant to teicoplanin (P<0.019). Univariate analysis revealed that hospitalization in intensive care unit (ICU) prior to infection was a risk factor for VRE infection development: 43.5% (n=10) VRE in comparison to 15.4% (n=4) VSE infection cases. For patients treated in ICU prior to infection E. faecium was found more often in comparison to E. faecalis (respectively 35.9%, n=14 and 0, P=0.002). 88.5% (n=23) of patients with VSE infection and 60.9% (n=14) with . [...].