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. 1984 Dec;20(6):1068–1075. doi: 10.1128/jcm.20.6.1068-1075.1984

Detection of methicillin-resistant Staphylococcus aureus by microdilution and disk elution susceptibility systems.

J M Boyce, L S Lytle, D A Walsh
PMCID: PMC271519  PMID: 6569873

Abstract

To determine whether methicillin-resistant (MR) Staphylococcus aureus from different geographic areas are detected reliably by various commercially available microdilution broth and disk elution systems, 73 such isolates obtained from hospitals in 13 cities were tested by a reference method (agar dilution) and by the Microscan, API 3600S, Autobac I, and MS-2 systems. Both Eugonic broth and Low Thymidine Eugonic broth were used in the evaluation of the Autobac I, and two versions of the MS-2 were used. The proportions of isolates categorized as MR by the various methods were: agar dilution method, 99%; Microscan, 100% (if the suggested cut-off of the manufacturer was used); API 3600S, 96%; Autobac I, 84 to 93%; and MS-2, 54 to 68%. With the MS-2 system, isolates from Jackson, Miss., were classified as susceptible to methicillin more often than were strains from other cities. With the Autobac I (Eugonic broth), only 55% of isolates from Houston, Tex., were classified as MR, whereas 89% of isolates from all other cities were correctly classified as MR. With the API 3600S, strains from some cities were categorized as nafcillin susceptible, whereas strains from other cities were classified as resistant to nafcillin. The results of this study suggest that future evaluations of antimicrobial susceptibility testing systems should include MR strains of S. aureus from several geographic areas.

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Selected References

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  1. Aldridge K. E., Janney A., Sanders C. V., Marier R. L. Interlaboratory variation of antibiograms of methicillin-resistant and methicillin-susceptible Staphylococcus aureus strains with conventional and commercial testing systems. J Clin Microbiol. 1983 Nov;18(5):1226–1236. doi: 10.1128/jcm.18.5.1226-1236.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Barnes W. G., Green L. R., Talley R. L. Clinical evaluation of automated antibiotic susceptibility testing with the MS-2 system. J Clin Microbiol. 1980 Oct;12(4):527–532. doi: 10.1128/jcm.12.4.527-532.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Barry A. L., Effinger L. J., Badal R. E. Short-term storage of six penicillins and cephalothin in microdilution trays for antimicrobial susceptibility tests. Antimicrob Agents Chemother. 1976 Jul;10(1):83–88. doi: 10.1128/aac.10.1.83. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Barry A. L., Jones R. N., Gavan T. L. Evaluation of the micro-media system for quantitative antimicrobial drug susceptibility testing: a collaborative study. Antimicrob Agents Chemother. 1978 Jan;13(1):61–69. doi: 10.1128/aac.13.1.61. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Bauer A. W., Kirby W. M., Sherris J. C., Turck M. Antibiotic susceptibility testing by a standardized single disk method. Am J Clin Pathol. 1966 Apr;45(4):493–496. [PubMed] [Google Scholar]
  6. Benner E. J., Kayser F. H. Growing clinical significance of methcillin-resistant Staphylococcus aureus. Lancet. 1968 Oct 5;2(7571):741–744. doi: 10.1016/s0140-6736(68)90947-1. [DOI] [PubMed] [Google Scholar]
  7. Boyce J. M. Reevaluation of the ability of the standardized disk diffusion test to detect methicillin-resistant strains of Staphylococcus aureus. J Clin Microbiol. 1984 Jun;19(6):813–817. doi: 10.1128/jcm.19.6.813-817.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Boyce J. M., White R. L., Bonner M. C., Lockwood W. R. Reliability of the MS-2 system in detecting methicillin-resistant Staphylococcus aureus. J Clin Microbiol. 1982 Feb;15(2):220–225. doi: 10.1128/jcm.15.2.220-225.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Carlson J. R., Conley F. E., Cahall D. L. Methicillin-resistant Staphylococcus aureus susceptibility testing with Abbott MS-2 system. Antimicrob Agents Chemother. 1982 Apr;21(4):676–677. doi: 10.1128/aac.21.4.676. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Chitwood L. A. Tube dilution antimicrobial susceptibility testing: efficacy of a microtechnique applicable to diagnostic laboratories. Appl Microbiol. 1969 May;17(5):707–709. doi: 10.1128/am.17.5.707-709.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Cleary T. J., Maurer D. Methicillin-resistant Staphylococcus aureus susceptibility testing by an automated system, Autobac I. Antimicrob Agents Chemother. 1978 May;13(5):837–841. doi: 10.1128/aac.13.5.837. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Degener J. E., Thonus I. P., Michel M. F. The antimicrobial susceptibility test: a comparison of the results of four methods. J Appl Bacteriol. 1981 Jun;50(3):505–517. doi: 10.1111/j.1365-2672.1981.tb04253.x. [DOI] [PubMed] [Google Scholar]
  13. Funnell G. R., Guinness M. D. Australian evaluation of Autobac I with suggested interpretive and technical modifications. Antimicrob Agents Chemother. 1979 Sep;16(3):255–261. doi: 10.1128/aac.16.3.255. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gavan T. L., Jones R. N., Barry A. L. Evaluation of the Sensititre system for quantitative antimicrobial drug susceptibility testing: a collaborative study. Antimicrob Agents Chemother. 1980 Mar;17(3):464–469. doi: 10.1128/aac.17.3.464. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Gavan T. L., Town M. A. A microdilution method for antibiotic susceptibility testing: an evaluation. Am J Clin Pathol. 1970 Jun;53(6):880–885. doi: 10.1093/ajcp/53.6.880. [DOI] [PubMed] [Google Scholar]
  16. Genta V. M., McCarthy L. R., Herrick M., Rose F. Evaluation of the Titertek Multiskan for determining minimal inhibitory concentration endpoints. Antimicrob Agents Chemother. 1982 Jul;22(1):151–153. doi: 10.1128/aac.22.1.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Gerlach E. H., Jones R. N., Barry A. L. Collaborative evaluation of the microbial profile system for quantitative antimicrobial susceptibility testing. J Clin Microbiol. 1983 Mar;17(3):436–444. doi: 10.1128/jcm.17.3.436-444.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Goss W. A., Cimijotti E. B. Evaluation of an automatic diluting device for microbiological applications. Appl Microbiol. 1968 Sep;16(9):1414–1416. doi: 10.1128/am.16.9.1414-1416.1968. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Haley R. W., Hightower A. W., Khabbaz R. F., Thornsberry C., Martone W. J., Allen J. R., Hughes J. M. The emergence of methicillin-resistant Staphylococcus aureus infections in United States hospitals. Possible role of the house staff-patient transfer circuit. Ann Intern Med. 1982 Sep;97(3):297–308. doi: 10.7326/0003-4819-97-3-297. [DOI] [PubMed] [Google Scholar]
  20. Hansen S. L., Freedy P. K. Concurrent comparability of automated systems and commercially prepared microdilution trays for susceptibility testing. J Clin Microbiol. 1983 May;17(5):878–886. doi: 10.1128/jcm.17.5.878-886.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Harris P. C., Sealey L. B. Two-hospital study of Staphylococcus aureus susceptibility to penicillin and ampicillin by Autobac I. Antimicrob Agents Chemother. 1980 Dec;18(6):922–925. doi: 10.1128/aac.18.6.922. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Harwick H. J., Weiss P., Fekety F. R., Jr Application of microtitration techniques to bacteriostatic and bactericidal antibiotic susceptibility testing. J Lab Clin Med. 1968 Sep;72(3):511–516. [PubMed] [Google Scholar]
  23. Jacob C. V., Kleineman J. Comparison of drug sensitivity testing with microdilution quantitative minimum inhibitory concentration and the Autobac I system. J Clin Microbiol. 1980 May;11(5):465–469. doi: 10.1128/jcm.11.5.465-469.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Jones R. N., Barry A. L., Bigelow J., Gavan T. L., Thornsberry C. Evaluation of the MICUR system for quantitative antimicrobial susceptibility testing: a multiphasic comparison with reference methods. J Clin Microbiol. 1982 Jul;16(1):153–163. doi: 10.1128/jcm.16.1.153-163.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Jones R. N., Edson D. C. Interlaboratory performance of disk agar diffusion and dilution antimicrobial susceptibility tests, 1979-1981. A summary of the microbiology portion of the College of American Pathologists (CAP) surveys. Am J Clin Pathol. 1982 Oct;78(4 Suppl):651–658. [PubMed] [Google Scholar]
  26. Jones R. N., Gavan T. L., Barry A. L. Evaluation of the sensititre microdilution antibiotic susceptibility system against recent clinical isolates: three-laboratory collaborative study. J Clin Microbiol. 1980 Apr;11(4):426–429. doi: 10.1128/jcm.11.4.426-429.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Jones R. N., Thornsberry C., Barry A. L., Gavan T. L. Evaluation of the Sceptor microdilution antibiotic susceptibility testing system: a collaborative investigation. J Clin Microbiol. 1981 Jan;13(1):184–194. doi: 10.1128/jcm.13.1.184-194.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Lindsey N. J., Barnes W. G. Examination of major disagreements in susceptibility test results by Autobac-1 and MS-2. Antimicrob Agents Chemother. 1981 Jul;20(1):115–119. doi: 10.1128/aac.20.1.115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. MacLowry J. D., Jaqua M. J., Selepak S. T. Detailed methodology and implementation of a semiautomated serial dilution microtechnique for antimicrobial susceptibility testing. Appl Microbiol. 1970 Jul;20(1):46–53. doi: 10.1128/am.20.1.46-53.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. MacLowry J. D., Marsh H. H. Semiautomatic microtechnique for serial dilution-antibiotic sensitivity testing in the clinical laboratory. J Lab Clin Med. 1968 Oct;72(4):685–687. [PubMed] [Google Scholar]
  31. Marymont J. H., Jr, Wentz R. M. Serial dilution antibiotic sensitivity testing with the microtitrator system. Am J Clin Pathol. 1966 May;45(5):548–551. doi: 10.1093/ajcp/45.5.548. [DOI] [PubMed] [Google Scholar]
  32. McKinley G. A., Fagerberg D. J., George B. A. Laboratory evaluation of the Anderson Technical semiautomated susceptibility testing system. Antimicrob Agents Chemother. 1981 Dec;20(6):777–782. doi: 10.1128/aac.20.6.777. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Mogyoros M., Morgan J. R., Smith J. A. Evaluation of the Autobac 1 susceptibility testing system in a clinical diagnostic laboratory. Antimicrob Agents Chemother. 1977 Apr;11(4):750–752. doi: 10.1128/aac.11.4.750. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Phillips I., Warren C., Waterworth P. M. Determination of antibiotic sensitivities by the Sensititre system. J Clin Pathol. 1978 Jun;31(6):531–535. doi: 10.1136/jcp.31.6.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Polk E. A., Starr A. J., Friedman H., Erb L. Comparison of lyophilized and frozen microtiter systems for routine MIC testing in the clinical laboratory. Am J Clin Pathol. 1982 Aug;78(2):223–228. doi: 10.1093/ajcp/78.2.223. [DOI] [PubMed] [Google Scholar]
  36. Pykett A. H. An assessment of the Sensititre method for determining minimum inhibitory and bactericidal concentrations. J Clin Pathol. 1978 Jun;31(6):536–538. doi: 10.1136/jcp.31.6.536. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Reeves D. S., Holt A., Bywater M. J., Wise R., Logan M. N., Andrews J. M., Broughall J. M. Comparison of sensititre dried microtitration trays with a standard agar method for determination of minimum inhibitory concentrations of antimicrobial agents. Antimicrob Agents Chemother. 1980 Dec;18(6):844–852. doi: 10.1128/aac.18.6.844. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Stubbs K. G., Wicher K. Laboratory evaluation of an automated antimicrobial susceptibility system. Am J Clin Pathol. 1977 Dec;68(6):769–777. doi: 10.1093/ajcp/68.6.769. [DOI] [PubMed] [Google Scholar]
  39. Thornsberry C., Anhalt J. P., Washington J. A., 2nd, McCarthy L. R., Schoenknecht F. D., Sherris J. C., Spencer H. J. Clinical laboratory evaluation of the Abbott MS-2 automated antimicrobial susceptibility testing system: report of a collaborative study. J Clin Microbiol. 1980 Sep;12(3):375–390. doi: 10.1128/jcm.12.3.375-390.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Thornsberry C., Gavan T. L., Sherris J. C., Balows A., Matsen J. M., Sabath L. D., Schoenknecht F., Thrupp L. D., Washington J. A., 2nd Laboratory evaluation of a rapid, automatic susceptibility testing system: report of a collaborative study. Antimicrob Agents Chemother. 1975 Apr;7(4):466–480. doi: 10.1128/aac.7.4.466. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Thornsberry C., McDougal L. K. Successful use of broth microdilution in susceptibility tests for methicillin-resistant (heteroresistant) staphylococci. J Clin Microbiol. 1983 Nov;18(5):1084–1091. doi: 10.1128/jcm.18.5.1084-1091.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Tilton R. C., Isenberg H. D. Evaluation of the performance parameters of a prediluted, quantitative antibiotic susceptibility test device. Antimicrob Agents Chemother. 1977 Feb;11(2):271–276. doi: 10.1128/aac.11.2.271. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Tilton R. C., Isenberg H. D. In-use evaluation of a prediluted quantitative antibiotic susceptibility test device. Antimicrob Agents Chemother. 1977 Oct;12(4):470–473. doi: 10.1128/aac.12.4.470. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Tilton R. C., Lieberman L., Gerlach E. H. Microdilution antibiotic susceptibility test: examination of certain variables. Appl Microbiol. 1973 Nov;26(5):658–665. doi: 10.1128/am.26.5.658-665.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Tippett L. O., Zeleznick L. D., Robb C. A. Modification of the microtiter technique for antimicrobial drug susceptibility testing by incorporation of indicators. Appl Microbiol. 1970 Sep;20(3):342–345. doi: 10.1128/am.20.3.342-345.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Urban T., Jarstrand C. Rapid determination of the susceptibility of bacteria to antibiotics with Sensititre plates and nitroblue tetrazolium. J Antimicrob Chemother. 1981 Nov;8(5):363–369. doi: 10.1093/jac/8.5.363. [DOI] [PubMed] [Google Scholar]
  47. Witebsky F. G., Maclowry J. D., French S. S. Broth dilution minimum inhibitory concentrations: rationale for use of selected antimicrobial concentrations. J Clin Microbiol. 1979 May;9(5):589–595. doi: 10.1128/jcm.9.5.589-595.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Woolfrey B. F., Ramadei W. A., Quall C. O. Evaluation of a semiautomated micro-broth dilution system for determing minimum inhibitory concentrations of antimicrobics. Am J Clin Pathol. 1980 Mar;73(3):374–379. doi: 10.1093/ajcp/73.3.374. [DOI] [PubMed] [Google Scholar]

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