Antibiotic Resistant Patterns of Enterococcus Species Isolated from Clinical Samples in a Nigerian Private Tertiary Medical Centre
Keywords:
Clinical Samples, Enterococci, Resistant PatternsAbstract
Enterococci cause serious nosocomial infections which are characteristically associated with high mortality rates and treatment challenges because the bacteria are not only innately resistant to some antibiotics but also possess the ability to develop acquired resistance to virtually all clinically beneficial antimicrobial agents. This study was carried out to determine the antibiotics resistant patterns among isolates of Enterococci from clinical samples so as to provide knowledge that will inform the appropriate antimicrobial choice for its infections in this setting. It was a descriptive, cross-sectional retrospective study conducted over a period of 18 months (February 2024 – August 2025) at the medical microbiology laboratory of Nisa Premiers Hospital. Laboratory records of all Enterococci isolated from various clinical specimens submitted for culture as well as their susceptibility rates to variously tested antibiotics were extracted, reviewed and analyzed., Specimen culture and antimicrobial sensitivity testing of isolates were performed following standard microbiological methods. Forty-one (41) isolates of Enterococci were recovered from the various clinical samples processed. Thirty-five (85.4%) of all the isolates were Enterococcus faecalis, while 6 (14.6%) were Enterococcus faecium. Enterococci were most frequently isolated from urine 36 (87.8%). The prevalence rate of vancomycin-resistant Enterococcus (VRE) was 27.5%. Enterococcus was highly resistant to ciprofloxacin (85.7%) and doxycycline (57.9%), relatively highly resistant to linezolid (25%), but displayed the least resistance to nitrofurantoin (18.7%). In conclusion, the most frequent enterococcal infection was UTI, and Enterococcus faecalis was the most frequent species causing infections in this study. There were relatively high prevalence rates of both VRE and Linezolid-resistant Enterococcus. There is, therefore, a need for strengthening of antimicrobial stewardship program, implementation of infection control measures and routine surveillance in order to reduce the emergence of resistant strain and control its spread.
References
1. García-Solache M, Rice LB. The Enterococcus: a Model of Adaptability to Its Environment. Clin Microbiol Rev. 2019;32(2):e00058-18. doi: 10.1128/CMR.00058-18. PMID: 30700430; PMCID: PMC6431128.
2. Sabina Y, Rameez Y, Soma B, Indrani B. Study of enterococcus physiology and their characteristics- A short review. Journal of Dental and Medical Sciences. 2022;21(4): 24–29. DOI: 10.9790/0853-2104122429
3. Krishna KV, Koujalagi K, Surya RU, Namratha MP, Malaviya A. Enterococcus species and their probiotic potential: Current status and future prospects. J App Biol Biotech. 2023;11(1):36-44. DOI: 10.7324/JABB.2023.110105-1
4. Zhen X, Lundborg CS, Sun X, Hu X, Dong H. Economic burden of antibiotic resistance in ESKAPE organisms: a systematic review. Antimicrob Resist Infect Control. 2019; 8:137.
5. Wang JT, Chang SC, Wang HY, Chen PC, Shiau YR & Lauderdale TL. High rates of multidrug resistance in Enterococus faecalisandE. faeciumisolated from inpatients in Taiwan. Diagn. Microbiol. Infect.2013;75 (4):406 – 411
6. Zhang Y, Du M, Chang Y, Chen LA & Zhang Q. .Incidence, clinical characteristics, and outocmes of nosocomial Enterococcusspp. bloodstream infections in a tertiary-care hospital in Beijing, china: a four-year retrospective study. Antimicrob. Resist. Infect. Control 2017;6 (1);1–11
7. Sparo M, Delpech G & García Allende N. Impact on public health of the spread of high-level resistance to gentamicin-andvancomycin in enterococci. Front. Microbiol. 2018;9;3073
8. Sachan S & Anubhaw A. Species prevalence, antimicrobial susceptibility of enterococci isolated from various clinical samples in tertiary care hospital. International Journal of Health Sciences. 2022; 6:4507-4514.
9. Klare I, Fleige C, Geringer U, Thürmer A, Bender J, Mutters NT. Increased frequency of linezolid resistance among clinical Enterococcus faecium isolates from German hospital patients. J Glob Antimicrob Resist. 2015;3: 128-31. 10.1016/j.jgar.2015.02.007.
10. Gangurde N, Mane M, Phatale S. Prevalence of multidrug resistant Enterococci in a tertiary care hospital in India: a growing threat. Open J Med Microbiol. 2014;4(1):11. doi: 10.4236/ojmm.2014.41002.
11. Deshpande VR, Karmarkar MG, Mehta PR. Prevalence of multidrug-resistant enterococci in a tertiary care hospital in Mumbai, India. J Infect Dev Ctries. 2013;7(2):155–158. doi: 10.3855/jidc.3018.
12. Collee JG, Fraser AG, Marmion BP, Simmons A. Mackie and McCartney Practical Medical Microbiology 1996 14th ed Edinburg Churchill Livingstone:263–74
13. Fingold SM, Baron EJ. Diagnostic microbiology. 10th Ed. Toronto, St-Louis: Moby Company: pp.150-170.
14. CLSI: Performance Standards for Antimicrobial Susceptibility Testing: 29th edition. CLSI supplement M100. Wayne, PA: Clinical and Laboratory Standards Institute; 2019.
15. Victor NA, Grace MI, Chijioke PA. Enterococcus Isolates in Clinical Samples from In-patients in Uyo, Nigeria. International Journal of Life Sciences Research. 2019;7(1): 353-358
16. Arias CA, Murray BE. Emergence and management of drug-resistant Enterococcal infections. Expert Rev Anti Infect Ther. 2008;6(5):637–55,
17. Ndubuisi JC, Olonitola OS, Olayinka AT, Jatau ED & Iregbu KC. Prevalence and Antibiotics Susceptibility Profile of Enterococcus Species Isolated from some Hospitals in Abuja, Nigeria. Afr. J. Cln. Exper. Microbiol. 2017;18 (3): 154-158
18. Dauphin DM, Oluwole MD. Prevalence, antibiotic susceptibility pattern and risks of multiple drug-resistant Enterococcus species in Ojo, Lagos, Nigeria. N Y Sci J 2020;13(7):25-32]
19. Orababa OQ, Soriwei JD, Akinsuyi SO, Essiet UU, Solesi OM. A systematic review and meta-analysis on the prevalence of vancomycin-resistant enterococci (VRE) among Nigerians. Porto Biomed J. 2021;11;6(1):e125. doi: 10.1097/j.pbj.0000000000000125. PMID: 33884321; PMCID: PMC8055482
20. Abera A, Tilahun, M., Tekele SG and Belete MA. Prevalence, antimicrobial
susceptibility patterns, and risk factors associated with enterococci among pediatric
patients at Dessie Referral Hospital, Northeastern Ethiopia. BioMed Research
International, 2021: 5549847.
21. Mahajan M, Shinde R, Karande GS, Patil S. Prevalence of Enterococcus Species in Various Clinical Samples and Their Antimicrobial Susceptibility Pattern. Cureus 2024;16(11): e72836. DOI 10.7759/cureus.72836
22. Sannathimmappa MB, Nambiar V, Aravindakshan R, Al-Risi ES. Clinical Profile and Antibiotic Susceptibility Pattern of Enterococcus faecalis and Enterococcus faecium with an Emphasis on Vancomycin Resistance. Biomedical and Biotechnology Research Journal 2023;7(2): 283-287. DOI: 10.4103/bbrj.bbrj_38_23
23. Sachin MD, Jigar RK. Prevalence and Antimicrobial Susceptibility Pattern of Enterococcus Species Isolated in Clinical Samples from a Tertiary Care Centre. JPTCP. 2024;31(7): 357 – 362
24. Sava, G., Heikens, E. and Huebner, J. Pathogenesis and Immunity in Enterococcal Infections. Clinical Microbiology and Infection, 2010;16:533-540.http://dx.doi.org/10.1111/j.1469-0691.2010.03213.x
25. Wada Y, Harun AB, Yean CY, Zaidah AR. Vancomycin-Resistant Enterococci (VRE) in Nigeria: The First Systematic Review and Meta-Analysis. Antibiotics (Basel). 2020;9(9):565. doi: 10.3390/antibiotics9090565. PMID: 32882963; PMCID: PMC7558171.
26. Alemayehu, T., Hailemariam, M. Prevalence of vancomycin-resistant enterococcus in Africa in one health approach: a systematic review and meta-analysis. Sci Rep 2020;10;20542. https://doi.org/10.1038/s41598-020-77696-6
27. Toru M, Beyene G, Kassa T, Gizachew Z, Howe R, Yeshitila B. Prevalence and phenotypic characterization of Enterococcus species isolated from clinical samples of pediatric patients in Jimma University Specialized Hospital, south west Ethiopia. BMC Res Notes. 2018; 11:281. htps://doi.org/10.1186/s13104-018-3382-x
28. Razaz RN, Mohabati MA, Khoram AN, Shokoohizade L. Antibiotic Susceptibility of Staphylococcus aureus and Enterococcus Spp. Isolated from some Hospitals in Tehran. Med Lab J. 2015;9(2):78-84. FA
29. Khanal LK, Sujatha R, Kumar A, Bhatiani A and Singh DN. A study of clinical outcome, prevalence and molecular characterization of vancomycin resistant enterococci (VRE) at a tertiary care centre. Al Ameen J Med Sci 2021; 14(1):62-67.)
30. Olawale KO, Fadiora SO, Taiwo SS. Prevalence of hospital-acquired enterococci infections in two primary-care hospitals in osogbo, southwestern Nigeria. Afr J Infect Dis. 2011;5(2):40-6. doi: 10.4314/ajid.v5i2.66513. PMID: 23878706; PMCID: PMC3497844.
31. Beshiru A and Uwhuba EK. Abeni B and Kate EU. Prevalence, Molecular Characterization and Risk Factors of Vancomycin-Resistant Enterococci: Evidence from Patients Admitted in University of Benin Teaching Hospital, Benin City Nigeria. DUJOPAS 2023;9(3b): 311-321
32. Harshad SN, Anita EC, Harinandan M. Prevalence of various enterococcus species and their antibiotic resistance pattern among urinary isolates in tertiary care center in South Eastern Rajasthan. IP International Journal of Medical Microbiology and Tropical Diseases, 2019;5(1):18-22
33. Md SA, Md J & Rashedur R. Examining Antimicrobial Resistance in Enterococcus Species: A Single Center Cross-Sectional Study. Saudi J Pathol Microbiol, 2023; 8(10): 257-262
34. Mangukiya PD, Patel VA, Parmar AT. Prevalence of Enterococcus Species in Various Clinical Specimens and it's Antimicrobial Susceptibility Pattern in a Tertiary Care Teaching Hospital of Central Gujarat. GAIMS J Med Sci 2025;5(1):18-24
35. Ferede ZT, Tullu KD, Derese SG and Yeshanew AG Prevalence and antimicrobial susceptibility pattern of Enterococcus species isolated from different clinical samples at Black Lion Specialized Teaching Hospital, Addis Ababa, Ethiopia. BMC Res Notes 2018;11:793:https://doi.org/10.1186/s13104-018-3898-0.
