ABSTRACT
BACKGROUND & OBJECTIVES: Vancomycin-resistant enterococci (VRE) have become one of the most challenging nosocomial pathogens with the rapid spread of the multi-drug resistant strain with limited therapeutic options. It is a matter of concern due to its ability to transfer vancomycin resistant gene to other organisms. The present study was undertaken to determine the emergence of vancomycin-resistant enterococci and the vanA gene among the isolates in a tertiary care hospital of North-East India. METHODS: A total of 67 consecutive enterococcal isolates from different clinical samples were collected and identified by using the standard methods. Antibiogram was done by disk diffusion method and VRE was screened by the disk diffusion and vancomycin supplement agar dilution method. The minimum inhibitory concentration (MIC) value for vancomycin was determined by E-test. The VRE isolates were analyzed by PCR for vanA gene. RESULTS: A total of 54 (81%) Enterococcus faecalis and 13 (19%) E. faecium were detected among the clinical isolates and 16 (24%) were VRE. The VRE isolates were multidrug resistant and linezolid resistance was also found to be in three. MIC range to vancomycin was 16-32 µg/ml among the VRE. The vanA gene was found in nine of 16 VRE isolates. INTERPRETATION & CONCLUSIONS: Emergence of VRE and presence of vanA in a tertiary care hospital setting in North-East India indicate toward a need for implementing infection control policies and active surveillance.
Subject(s)
Bacterial Proteins/genetics , Carbon-Oxygen Ligases/genetics , Cross Infection/epidemiology , Enterococcus faecalis/isolation & purification , Vancomycin-Resistant Enterococci/genetics , Bacterial Proteins/blood , Bacterial Proteins/urine , Carbon-Oxygen Ligases/blood , Carbon-Oxygen Ligases/urine , Cross Infection/drug therapy , Cross Infection/genetics , Cross Infection/microbiology , Drug Resistance, Multiple/genetics , Enterococcus faecalis/drug effects , Enterococcus faecalis/pathogenicity , Humans , India , Microbial Sensitivity Tests , Tertiary Care Centers , Vancomycin/therapeutic use , Vancomycin-Resistant Enterococci/isolation & purification , Vancomycin-Resistant Enterococci/pathogenicityABSTRACT
Extended-spectrum ß-lactamases (ESBLs) are rapidly evolving group of ß-lactamase enzymes produced by the Gram negative bacteria. In this study, we determined the antimicrobial sensitivity pattern of Escherichia coli isolates and prevalence of TEM, SHV and CTX-M genes in ESBL positive E. coli isolated from the patients admitted to a tertiary care hospital in North-East India. A total of 85 multidrug-resistant isolates of E. coli obtained from clinical samples; urine (n = 80), sputum (n = 3), body fluid (n = 1), vaginal discharge (n = 1) were screened for resistance to third generation cephalosporins. ESBL production in resistant isolates was determined by double disk synergy test (DDST) and phenotypic confirmatory test (PCT). ESBL positive isolates were subjected to PCR for detection of TEM, SHV and CTX-M genes. Imipenem was found to be most effective against E. coli (susceptible isolates 96.47%) while ciprofloxacin was the least effective antibiotic (resistant isolates 60%). Among 33 ESBL positive isolates confirmed via PCT, preponderance in female population (60.6%) was noted. The most prevalent gene was bla(SHV) (63.04%) followed by bla(TEM) and bla(CTX-M) (60.86 and 54.34%, respectively) in ESBL positive E. coli. Most of the extensively used antibiotics, appear to be ineffective against the ever-mutating bacteria. This resistance urges cautious antimicrobial management on priority. Further, it helps in effectively designing the chemotherapeutic regimen for patients of a particular geographic area.
Subject(s)
Escherichia coli/enzymology , beta-Lactamases/analysis , Adult , Drug Resistance, Bacterial , Escherichia coli/drug effects , Female , Humans , Male , Middle Aged , Tertiary Healthcare , beta-Lactamases/geneticsABSTRACT
The emergence of multidrug-resistant and vancomycin-resistant enterococci during the last decade has made it difficult to treat nosocomial infections. Although various enterococcal species have been identified, only two (Enterococcus faecalis and Enterococcus faecium) are responsible for the majority of human infections. Vancomycin is an important therapeutic alternative against multidrug-resistant enterococci but is associated with a poor prognosis. Resistance to vancomycin dramatically reduces the therapeutic options for enterococcal infections. The bacterium develops resistance by modifying the C-terminal d-alanine of peptidoglycan to d-lactate, creating a d-Ala-d-Lac sequence that effectively reduces the affinity of vancomycin for the peptidoglycan by 1000-fold. Moreover, the resistance genes can be transferred from enterococci to Staphylococcus aureus, thereby posing a threat to patient safety and also a challenge for treating physicians. Judicious use of vancomycin and broad-spectrum antibiotics must be implemented, but strict infection control measures must also be followed to prevent nosocomial transmission of these organisms. Furthermore, improvements in clinical practice, rotation of antibiotics, herbal drugs, nanoantibiotics and the development of newer antibiotics based on a pharmacogenomic approach may prove helpful to overcome dreadful vancomycin-resistant enterococcal infections.
