Original Research Article Indian J Microbiol Res 2016;3(1):77-81 77 Speciation of Enterococcal Isolates in a Tertiary Care Hospital and Molecular Characterisation of Vancomycin Resistant Enterococci (VRE) Dineshraj Ravi 1 , Vasanthi Rompicherla 2 , Gowthami Govindan 3 , Priyadarshini Shanmugam 4,* 1,3 Post Graduate Student, 2 Associate Professor, 4 Professor Dept. of Microbiology, Chettinad Hospital and Research Institute, Chennai *Corresponding Author E-mail: priyadarshini0018@gmail.com Abstract Background: Enterococci are gram positive cocci which reside as commensal microbial flora in gastrointestinal tract, vagina, biliary tract and male urethra. E.faecalis is the predominant species followed by E.faecium. Resistance against glycopeptides and aminoglycosides are being increasingly demonstrated and that is conferred upon largely by van A gene. Aims: To isolate and speciate Enterococci from various clinical samples, antibiogram pattern determination, followed by genotyping of vancomycin resistant Enterococci. Settings and Design: Prospective study. Materials and Methods: 200 Enterococcal isolates were collected and processed for speciation based on battery of phenotypic characteristics. Antibiotic sensitivity testing was performed as per CLSI guidelines 2014 for glycopeptide and aminoglycoside antibiotics. Enterococci which were resistant to vancomycin were subjected to polymerase chain reaction for van A gene detection. Statistical analysis used: Nil. Results: Of the 200 isolates 5 were resistant to vancomycin and teicoplanin (2.5%), 30 were resistant to high level gentamicin (15%). van A gene was detected in 3 of the 5 vancomycin resistant isolates. E.faecium was observed to be more resistant to the antimicrobials. Conclusions: If the vancomycin resistance in Enterococci gets dispersed throughout the world, it may pose a challenge in the treatment of Gram positive infections and may lead to treatment failure. Further treatment options may not be available. Hence these infections have to be prevented and the sequence of development of resistance to higher drugs has to be controlled by active surveillance and prevention. Key-words: E.faecalis, E.faecium, High-level Gentamicin resistance, Vancomycin-resistance, Van A gene Key Messages: Implementation of vigorous surveillance and provision of timely data Access this article online Quick Response Code: Website: www.innovativepublication.com DOI: 10.5958/2394-5478.2016.00019.4 Introduction Enterococci are Gram positive cocci, belonging to group-D streptococci and comprise of 37 species; they usually inhabit the gastrointestinal as part of the commensal microbial flora. The predominant species are Enterococcus faecalis (85-90%) and Enteroccoccus faecium (5-10%) -[1] . E.avium, E.casseliflavus, E.durans, E.cecorum, E.gallinarum, E.malodoratus, E.raffinosus, E.hirae, E.dispar and E.mundtii are rarely isolated in humans -[2] . Enterococcus isolated from nosocomial infections acquires resistance particularly against glycopeptides -[3] . Enterococci cause urinary tract infection, wound infection, biliary tract infection and occasionally meningitis, bacteraemia and endocarditis - [1] . This organism resides in biliary tract, vagina and male urethra. The most worrisome issue is that it shows intrinsic resistance to most of the beta-lactam antibiotics, low level resistance to aminoglycosides and intermediate-resistance to fluoroquinolones. The resistance was more with E.faecium than E.faecalis -[1] . Avoparcin use in animal feeds has lead to the emergence of vancomycin-resistant enterococci and vancomycin-resistance has been tranferred to methicillin-resistant Staphylococcus aureus -[4] . Enterococcus faecium isolates of hospital origin holds a subsidiary genetic expression that may play a role in virulence -[5] . Nine genes have been identified that ascertain vancomycin resistance namely: van A, B, C, D, E, G, L, M and N. van A type takes the lead globally and imparts a high level of resistance to glycopeptide antibiotics seen particularly in vancomycin-resistant Enterococcus faecium -[6] . Genotype van A is prevalent in E.faecium while van B prevalent in E.faecalis -[6] . The study was conducted to isolate and identify Enterococci from the clinical samples followed by speciation. Further antibiotic sensitivity testing was performed for determining the sensitivity pattern and