Skip to main content
Antimicrobial Agents and Chemotherapy logoLink to Antimicrobial Agents and Chemotherapy
. 1991 Sep;35(9):1911–1913. doi: 10.1128/aac.35.9.1911

Emergence of quinolone resistance among clinical isolates of methicillin-resistant Staphylococcus aureus in Ontario, Canada.

N Harnett 1, S Brown 1, C Krishnan 1
PMCID: PMC245290  PMID: 1952866

Abstract

One hundred two isolates of methicillin-resistant Staphylococcus aureus (MRSA) randomly selected from across the Canadian province of Ontario were tested for their susceptibility to ciprofloxacin, norfloxacin, and nalidixic acid by the agar dilution method. Forty-nine percent (50 of 102) had high levels of resistance to these quinolone compounds. For the 50 resistant isolates, ciprofloxacin and norfloxacin had high MICs for 90% of isolates (MIC90s) of 128 micrograms/ml and greater than 128 microgram/ml, respectively; for these isolates, the nalidixic acid MIC90 was greater than 640 micrograms/ml. The majority (98%) of the 50 isolates were also resistant to tobramycin (MIC90, greater than 128 micrograms/ml), while 42% of the isolates were resistant to gentamicin (MIC90, 64 micrograms/ml). Quinolone-resistant MRSA isolates were susceptible to bacteriophages from several groups, indicating independent selection of resistant strains. These results suggest that a reappraisal of the use of fluoroquinolones against MRSA in Canada is necessary.

Full text

PDF
1913

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aldridge K. E., Janney A., Sanders C. V. Comparison of the activities of coumermycin, ciprofloxacin, teicoplanin, and other non-beta-lactam antibiotics against clinical isolates of methicillin-resistant Staphylococcus aureus from various geographical locations. Antimicrob Agents Chemother. 1985 Nov;28(5):634–638. doi: 10.1128/aac.28.5.634. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Goering R. V., Ruff E. A. Comparative analysis of conjugative plasmids mediating gentamicin resistance in Staphylococcus aureus. Antimicrob Agents Chemother. 1983 Sep;24(3):450–452. doi: 10.1128/aac.24.3.450. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Hooper D. C., Wolfson J. S., Ng E. Y., Swartz M. N. Mechanisms of action of and resistance to ciprofloxacin. Am J Med. 1987 Apr 27;82(4A):12–20. [PubMed] [Google Scholar]
  4. Maple P. A., Hamilton-Miller J. M., Brumfitt W. World-wide antibiotic resistance in methicillin-resistant Staphylococcus aureus. Lancet. 1989 Mar 11;1(8637):537–540. doi: 10.1016/s0140-6736(89)90076-7. [DOI] [PubMed] [Google Scholar]
  5. Schaefler S. Methicillin-resistant strains of Staphylococcus aureus resistant to quinolones. J Clin Microbiol. 1989 Feb;27(2):335–336. doi: 10.1128/jcm.27.2.335-336.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Shalit I., Berger S. A., Gorea A., Frimerman H. Widespread quinolone resistance among methicillin-resistant Staphylococcus aureus isolates in a general hospital. Antimicrob Agents Chemother. 1989 Apr;33(4):593–594. doi: 10.1128/aac.33.4.593. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Shanson D. C., Kensit J. C., Duke R. Outbreak of hospital infection with a strain of Staphylococcus aureus resistant to gentamicin and methicillin. Lancet. 1976 Dec 18;2(7999):1347–1348. doi: 10.1016/s0140-6736(76)91986-3. [DOI] [PubMed] [Google Scholar]
  8. Soussy C. J., Bouanchaud D. H., Fouace J., Dublanchet A., Duval J. A gentamycin resistance plasmid in Staphylococcus aureus. Ann Microbiol (Paris) 1975 Jul-Aug;126B(1):91–94. [PubMed] [Google Scholar]
  9. Ubukata K., Itoh-Yamashita N., Konno M. Cloning and expression of the norA gene for fluoroquinolone resistance in Staphylococcus aureus. Antimicrob Agents Chemother. 1989 Sep;33(9):1535–1539. doi: 10.1128/aac.33.9.1535. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Watanakunakorn C. Treatment of infections due to methicillin-resistant Staphylococcus aureus. Ann Intern Med. 1982 Sep;97(3):376–378. doi: 10.7326/0003-4819-97-3-376. [DOI] [PubMed] [Google Scholar]
  11. Weinstein R. A., Kabins S. A., Nathan C., Sweeney H. M., Jaffe H. W., Cohen S. Gentamicin-resistant staphylococci as hospital flora: epidemiology and resistance plasmids. J Infect Dis. 1982 Mar;145(3):374–382. doi: 10.1093/infdis/145.3.374. [DOI] [PubMed] [Google Scholar]
  12. Wolfson J. S., Hooper D. C. Fluoroquinolone antimicrobial agents. Clin Microbiol Rev. 1989 Oct;2(4):378–424. doi: 10.1128/cmr.2.4.378. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Antimicrobial Agents and Chemotherapy are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES