Diversity and Genetic Clonality of Vancomycin and Gentamicin Resistant Enterococci Isolated from Healthy Humans in Iran
,
Abstract
Background: This study was done to determine the level of high level gentamicin resistant (HLGR) and vancomycin resistant enterococci (VRE) in the healthy normal human population living in Tehran, Iran.
Methods: A total of 700 fecal samples were isolated from the period of September 2007 to September 2008 and the species were identified by the biochemical tests and PCR. Antibiotic susceptibility test, gentamicin and vancomycin resistant genes and the conjugation tests were performed to evaluate the transferability of the drug resistant genes. The clonality of the isolates was also determined by PFGE.
Results: The results showed that the prevalence of HLGR and VRE in the healthy normal population were 16.6% (100) and 1% (6) for HLGR and VRE, respectively. Amongst the HLGR enterococci, the most frequent species were found to be Enterococcus faecalis in 63% of the isolates. This was followed by E. faecium (33%), E. gallinarum (3%) and E. casseliflavus (1%). The frequency of the gentamicin resistant genes were 99 (99%), 91 (91%), 3(3%) and 1(1%) for aac(6')-Ie-aph(2'')-Ia, aph(3')-IIIa, ant(4')Ia and aph(2'')-Id genes, respectively. Among the vancomycin resistant genes, vanA was found in 1% (6) of isolates only. PFGE revealed high heterogeneity among the 63 E. faecalis strains and 33 E. faecium with 31 and 28 different patterns, respectively. The 6 VR E. faecium revealed 6 different patterns.
Conclusion: The prevalence and heterogenous populations of HLGR in the normal flora of the humans found here were higher than reports from many countries, may be suggestive of excessive antibiotic usage in Iranian.
2. Hancock LE, Gilmore MS. Pathogenicity of enterococci. Gram-Positive Pathogens book 2000; 25:251-8.
3. Marothi YA, Agnihotri H, Dubey D. Enterococcal resistance. Indian J Med Microbiol 2005; 23(4):214-9.
4. Tansuphasiri U, Khaminthakul D, Pandii W. Antibiotic resistance of enterococci isolated from frozen foods and environmental water. Southeast Asian J Trop Med Public Health 2006; 37(1):162-70.
5. McDonald LC, Kuehnert MJ, Tenover FC, et al. Vancomycin-resistant enterococci outside the health-care setting: prevalence, sources, and public health implications. Emerg Infect Dis 1997; 3(3):311-7.
6. Pootoolal J, Neu J, Wright GD. Glycopeptide antibiotic resistance. An Rev Tox 2002; 42:381-408.
7. Courvalin P. Genetics of glycopeptide resistance in gram positive pathogens. Int J Med Microbiol 2005; 294(8):479-86.
8. Vakulenko SB, Mobashery S. Versatility of aminoglycosides and prospects for their future. Clin Microbiol Rev 2003; 16(3):430-50.
9. Novais C, Coque TM, Sousa JC, et al. Antimicrobial resistance among fecal enterococci from healthy individuals in Portugal. Clin Microbiol Infect 2006; 12(11):1131-4.
10. Facklam RR, Collins MD. Identification of Enterococcus species isolated from human infections by a conventional test Scheme. J Clin Microbiol 1989; 27(4):731-4.
11. Talebi M, Rahimi F, Katouli M, et al. Prevalence and antimicrobial resistance of enterococcal species in sewage treatment plants in Iran. Water Air Soil Pollut 2007; 185(111):9435-8.
12. National committee for clinical laboratory standards. Performance standards for antimicrobial susceptibility testing, 11th informational supplement 2001, vol21. National Committee for Clinical Laboratory Standards, Wayn, Pa.
13. The Enterococcus research site. Total DNA purification from Enterococcus. http://W3. ouhsc.edu/Enterococcus/DNA Purification from Enterococcus.
14. Kariyama R, Mitsuhata R, Chow JW, et al. Simple and reliable multiplex PCR assay for surveillance isolates of vancomycin-resistant Enterococci. J Clin. Microbiol 2000; 38(8):3092-5.
15. Vakulenko SB, Donabedian SM, Voskresenskiy AM, et al. Multiplex PCR for detection of aminoglycoside resistance genes in enterococci. Antimicrob Agents Chemother 2003; 47(4):1423-6.
16. Schwartz DC, Contor CR. Separation of yeast chromosome sized DNAs by pulsed field gradient gel electrophoresis. Cell 1984; 37(1):67-75.
17. Tenover FV, Arbeit RD, Goering RV, et al. Interpreting chromosomal DNA restriction patterns produced by Pulsed Field Gel Electrophoresis: Criteria for bacterial strain typing. J Clin Microbiol 1995; 33(9): 2233-9.
18. Carlet G. The gut is the epicenter of antibiotic resistance. Antimicrob Resist Infect Control 2012; 1:39-45.
19. Saifi M, Pourshafie MR, Eshraghian MR, et al. Anti-microbial resistance of enterococci isolated from urinary tract infections in Iran. Iran Biomed J 2008; 12(3):185-90.
20. Rahimi F, Taleb M, Saifi M, et al. Distribution of enterococcal species and detection of vancomycin resistance genes by multiplex PCR in Tehran sewage. Iran Biomed J 2007; 11(3):161-7.
21. Feizabadi MM, Maleknejad P, Asgharzadeh A, et al. Prevalence of aminoglycoside-modifying enzymes genes among isolates of Enterococcus faecalis and Enterococcus faecium in Iran. Microb Drug Resist 2006; 12(4):265-8.
22. Shokoohizadeh L, Ekrami A, Labibzadeh M, et al. Antimicrobial resistance patterns and virulence factors of enterococci isolates in hospitalized burn patients. BMC Res Notes 2018; 11:1-5.
23. Balzereit-Scheuerlein F, Stephan R. Prevalence of colonization and resistance patterns of vancomycin-resistant enterococci in healthy, non-hospitalised persons in Switzerland. Swiss Med Wkly 2001; 131(19):280-2.
24. Kolar M, Pantucek R, Bardon J, et al. Occurrence of vancomycin-resistant enterococci in humans and animals in the Czech Republic between 2002 and 2004. J Med Microbiol 2005; 54(10):965-7.
25. Hasannejad Bibalan M, Eshaghi M, Sadeghi J, et al. Clonal Diversity in Multi Drug Resistant (MDR) Enterococci Isolated from Fecal Normal Flora. Int J Mol Cell Med 2015; 4(4):240-4.
26. Boost M, Lai L, Donoghue M. Drug resistance in fecal enterococci in Hong Kong. J Infect Chemother 2004; 10(6):326-30.
27. Saifi M, Soltan Dallal MM, Pourshafei MR, et al. High level resistance of Enterococcus faecium and E. faecalis isolated from municipal sewage treatment plants to gentamicin. Iranian J Publ Health 2008; 37(1):103-7.
28. Choukhachian M, Nahaei MR, Ahangarzadeh Rezaee M, et al. High-level Gentamicin Resistance and Detection of aac (6’)Ie-aph (2”)Ia Gene in Enterococci Isolated from Pediatric Hospital in Northwest of Iran. Arch Clin Infect Dis 2018; 13(5): e62921.
29. Daikos GL, Bamias G, Kattamis C, et al. Structures, locations, and transfer frequencies of genetic elements conferring high-level gentamicin resistance in Enterococcus faecalis isolates in Greece. Antimicrob Agents Chemother 2003; 47(12):3950-3.
| Files | ||
| Issue | Vol 8 No 1-2 (2019) | |
| Section | Original Articles | |
| Keywords | ||
| Antibiotic resistance Enterococcus PFGE Normal flora Vancomycin resistance genes. | ||
| Rights and permissions | |
|
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
