Assessment of Antibiotics Susceptibility Pattern of Vancomycin Resistant Enterococci Isolated from Clinical Specimens in Port Harcourt

Aim: The aim of this study was to assess the prevalence of vancomycin resistance among Enterococcal species isolated from clinical specimens of patients attending two hospitals in Port Harcourt, Rivers State.

Study Design: The study employs statistical analysis of the data and interpretation.

Place and Duration of Study: Two hospitals which are Meridian hospital Port Harcourt and University of Port Harcourt Teaching Hospital, located in the city of Port-Harcourt, Rivers State were used for this study. Specimen collection lasted for 3 weeks and the analysis was carried out daily and it lasted for six months.

Methodology: A total of one hundred and eighteen (118) urine and stool specimens (60 urine and 58 stool specimens) were collected from Fifty nine (59) patients for a period of three months from Meridian hospital and University of Port Harcourt Teaching Hospital, Port-Harcourt, Rivers State. The specimens collected were grouped inpatients and outpatients and were subjected to standard microbiological procedures which include standard plate counts, identification, and sensitivity testing using Kirby-Bauer disk diffusion method, Minimum inhibitory concentration and molecular identification of the isolates.

Results: A total of 48 enterococcal isolates were isolated from the different specimens (hospitalized and non-hospitalized patients) of urine and stool specimens. All Enterococcal isolates showed high level of resistance to Ceftazidime and Cefuroxime (100%) followed by cloxacillin (95.8%), augumentin (85.4%) and Ceftriaxone (75.0%). The isolates showed higher sensitive rates to Ofloxacin (95.5%), followed by Gentamicin (77.1%) and Vancomycin (39.6%). All Enterococal isolates from this study had a MAR index > 0.2. A total of the 48 Enterococci were isolated, the 23 (47.9%) isolates were identified as vancomyin resistant during this study were subjected to MIC (Minimum Inhibitory Concentration) for vancomycin as a confirmatory test. Of the 23 isolates, 12 isolates were vancomycin resistant with 11 isolates showing vancomycin MIC values of 8-16μg /ml (vancomycin intermediate).

Conclusion: Conclusively, this study revealed varying Antibiotic susceptibility pattern of the isolated bacteria. Treatment guidelines for use of antibiotics should be based on the hospital formulary and the sensitivity patterns is advocated. This should be reviewed occasionally to ensure rational use of antibiotics