Evaluation of the prevalence of Vancomycin- resistant Enterococci strains isolated from patients in the ICU in Kashan

Enterococcus is part of human and animal intestinal flora. The withdrawal of these bacteria from their original location causes infections such as bacteremia, endocarditis, and Urinary Tract Infection (UTI) in hospitalized patients. The aim of this study is to determine the prevalence of vancomycin-resistant Enterococci (VRE) strains and the phenotypes of the Van genes in Enterococcus isolated from rectal swabs of patients hospitalized in the Intensive Care Unit (ICU). Methods and Materials: In this cross-sectional study, 156 rectal-swab samples were collected from patients in three wards of ICUs in the Shahid Beheshti Hospital. Enterococcus was detected in samples with the Gram stain and biochemical tests. An antibiotic resistance test was done using CLSI criteria. Different types of vancomycin resistance genes were identified by the multiplex PCR technique.

Enterococcus was detected in 135 rectal-swab samples (86.5%). The prevalence of VRE strains was 42.9% (58 cases). The frequency of Van A and Van C genes were 69% and 6.9%, respectively. In this study neither of van B, D, E and G genes were observed. 59.2% of patients who consumed 3 to 4 types of antibiotics, and 35.4% of those who consumed 1 to 2 types of antibiotics, had VRE.

Our findings highlight that antibiotic consumption can lead to increasing the resistance phenotypes. The prevalence of VRE was indicated 3.6 times more in patients who had consumed antibiotics. Also, with increasing number of antibiotic consumption of 1-2 to 3-4 types, risk of antibiotic-resistant Enterococci increases 2.65 times.