Skip to main content
PMC home page
Journal of Clinical Microbiology logoLink to Journal of Clinical Microbiology
. 1994 Aug;32(8):1846–1849. doi: 10.1128/jcm.32.8.1846-1849.1994

Evaluation of Etest for rapid susceptibility testing of Mycobacterium chelonae and M. fortuitum.

S E Hoffner 1, L Klintz 1, B Olsson-Liljequist 1, A Bolmström 1
PMCID: PMC263889  PMID: 7989530

Abstract

Etest is a new concept for MIC determinations for antimicrobial agents that is based on a predefined antibiotic gradient on a plastic strip calibrated with a continuous logarithmic MIC scale covering 15 twofold dilutions. Etest was compared with a reference agar dilution method for susceptibility testing of clinical isolates of Mycobacterium chelonae and M. fortuitum. Results read after 3 days showed good agreement between MICs obtained with Etest and those obtained with the reference method within +/- 2 dilutions for 90% of all test combinations. All but one of the strains were inhibited by low concentrations of ciprofloxacin or amikacin. Susceptibility to clarithromycin, erythromycin, imipenem, rifampin, doxycycline, and fusidic acid was variable, and all strains were resistant to ceftazidime and trimethoprim. The results suggest that Etest is well suited for studies of drug resistance in rapidly growing mycobacteria.

Full text

PDF
1846

Images in this article

1847Image
on p.1847

Selected References

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

  1. Baker C. N., Stocker S. A., Culver D. H., Thornsberry C. Comparison of the E Test to agar dilution, broth microdilution, and agar diffusion susceptibility testing techniques by using a special challenge set of bacteria. J Clin Microbiol. 1991 Mar;29(3):533–538. doi: 10.1128/jcm.29.3.533-538.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Brown D. F., Brown L. Evaluation of the E test, a novel method of quantifying antimicrobial activity. J Antimicrob Chemother. 1991 Feb;27(2):185–190. doi: 10.1093/jac/27.2.185. [DOI] [PubMed] [Google Scholar]
  3. Casal M. J., Rodriguez F. C. In vitro susceptibility of Mycobacterium fortuitum and M. chelonei to sisomicin, gentamicin and tobramycin. Ann Microbiol (Paris) 1983 Nov-Dec;134B(3):451–454. [PubMed] [Google Scholar]
  4. Hoel T., Casals J. B., Eng J. In vitro antimicrobial susceptibility testing of rapidly growing mycobacteria using the tablet diffusion method: resistance pattern of Norwegian Mycobacterium fortuitum and Mycobacterium chelonae isolates. APMIS. 1993 Jan;101(1):27–32. [PubMed] [Google Scholar]
  5. Hoffner S. E., Hjelm U., Källenius G. Susceptibility of Mycobacterium malmoense to antibacterial drugs and drug combinations. Antimicrob Agents Chemother. 1993 Jun;37(6):1285–1288. doi: 10.1128/aac.37.6.1285. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hoffner S. E., Svenson S. B., Källenius G. Synergistic effects of antimycobacterial drug combinations on Mycobacterium avium complex determined radiometrically in liquid medium. Eur J Clin Microbiol. 1987 Oct;6(5):530–535. doi: 10.1007/BF02014241. [DOI] [PubMed] [Google Scholar]
  7. Jorgensen J. H., Howell A. W., Maher L. A. Quantitative antimicrobial susceptibility testing of Haemophilus influenzae and Streptococcus pneumoniae by using the E-test. J Clin Microbiol. 1991 Jan;29(1):109–114. doi: 10.1128/jcm.29.1.109-114.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Olsson-Liljequist B. E-Test as a routine MIC tool for reference work. Diagn Microbiol Infect Dis. 1992 Jul;15(5):479–482. doi: 10.1016/0732-8893(92)90094-a. [DOI] [PubMed] [Google Scholar]
  9. Stone M. S., Wallace R. J., Jr, Swenson J. M., Thornsberry C., Christensen L. A. Agar disk elution method for susceptibility testing of Mycobacterium marinum and Mycobacterium fortuitum complex to sulfonamides and antibiotics. Antimicrob Agents Chemother. 1983 Oct;24(4):486–493. doi: 10.1128/aac.24.4.486. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Swenson J. M., Thornsberry C., Silcox V. A. Rapidly growing mycobacteria: testing of susceptibility to 34 antimicrobial agents by broth microdilution. Antimicrob Agents Chemother. 1982 Aug;22(2):186–192. doi: 10.1128/aac.22.2.186. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Swenson J. M., Wallace R. J., Jr, Silcox V. A., Thornsberry C. Antimicrobial susceptibility of five subgroups of Mycobacterium fortuitum and Mycobacterium chelonae. Antimicrob Agents Chemother. 1985 Dec;28(6):807–811. doi: 10.1128/aac.28.6.807. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Wallace R. J., Jr, Dalovisio J. R., Pankey G. A. Disk diffusion testing of susceptibility of Mycobacterium fortuitum and Mycobacterium chelonei to antibacterial agents. Antimicrob Agents Chemother. 1979 Nov;16(5):611–614. doi: 10.1128/aac.16.5.611. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Welch D. F., Kelly M. T. Antimicrobial susceptibility testing of Mycobacterium fortuitum complex. Antimicrob Agents Chemother. 1979 Jun;15(6):754–757. doi: 10.1128/aac.15.6.754. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Clinical Microbiology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES