Prevalence and Antibiotic Resistance Patterns of Isolated Enterococci from Hospitals of Zanjan City

Enterococci lead to many problems in terms of treatment failure and mortality in patients especially due to antibacterial resistance. Identification of antibiotic resistance in community is of extreme importance to prevent failures particularly in the treatment of infections. Therefore, this study intended to screen antibiotic-resistant enterococci samples from patients. Samples were collected from feces and blood of patients hospitalized over a period of 9 months from July 2013 to March 2014 in Vali-e Asr and Mousavi hospitals. Diagnostic tests such as growth in the presence of bile esculin agar and NaCl 6.5% as well as catalase and Gram staining were performed to verify the samples. Agar disk diffusion method for antibiotic susceptibility testing and microtitre plate assay was performed to evaluate the MIC of vancomycin. Among the tested antibiotics, ciprofloxacin showed the highest and teicoplanin as well as vancomycin exhibited the least antibiotic resistance. Interestingly, vancomycin minimum inhibitory concentration was determined 5 to 50 &mug/ml. In our study, isolated enterococci from the hospitalized patients showed relatively high resistance to majority of antibiotics. Meanwhile, antibiotic resistance to teicoplanin and vancomycin were acceptable in comparison to other similar studies.