Skip to main content
PMC home page
Antimicrobial Agents and Chemotherapy logoLink to Antimicrobial Agents and Chemotherapy
. 1990 Sep;34(9):1648–1654. doi: 10.1128/aac.34.9.1648

Collaborative investigation of variables in susceptibility testing of yeasts.

M A Pfaller 1, M G Rinaldi 1, J N Galgiani 1, M S Bartlett 1, B A Body 1, A Espinel-Ingroff 1, R A Fromtling 1, G S Hall 1, C E Hughes 1, F C Odds 1, et al.
PMCID: PMC171899  PMID: 2285276

Abstract

A multicenter study was performed to evaluate the effect of medium, incubation time (24 and 48 h), and temperature (30 and 35 degrees C) on intra- and interlaboratory variations in MICs of flucytosine, amphotericin B, and ketoconazole for yeasts. Testing was performed on coded isolates of Candida species (11 strains) and Cryptococcus neoformans (2 strains) by using a standard macrodilution protocol 11 laboratories. Four chemically defined media buffered to pH 7.0 with morpholinepropanesulfonic acid were evaluated, including buffered yeast nitrogen base, synthetic amino acid medium-fungal, RPMI 1640 medium, and high-resolution antifungal assay medium. Intralaboratory variability was less than or equal to fourfold for 97% of the replicate sets of data. The highest level of interlaboratory agreement, irrespective of antifungal agent or incubation conditions, was observed with RPMI 1640 medium. Intralaboratory variability was less than or equal to fourfold for 93% of the determinations with ketoconazole and 100% with flucytosine tested in RPMI 1640 medium at 35 degrees C for 24 h. Variability in amphotericin B results was less than or equal to fourfold for 81% of the determinations in RPMI 1640 medium at 35 degrees C for 48 h. The rank order of MICs within each antifungal test group was similar among the various laboratories and was generally in agreement with the reference rank order regardless of the test medium that we used.

Full text

PDF
1650

Selected References

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

  1. Block E. R., Jennings A. E., Bennett J. E. Variables influencing susceptibility testing of Cryptococcus neoformans to 5-fluorocytosine. Antimicrob Agents Chemother. 1973 Oct;4(4):392–395. doi: 10.1128/aac.4.4.392. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Calhoun D. L., Galgiani J. N. Analysis of pH and buffer effects on flucytosine activity in broth dilution susceptibility testing of Candida albicans in two synthetic media. Antimicrob Agents Chemother. 1984 Sep;26(3):364–367. doi: 10.1128/aac.26.3.364. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Calhoun D. L., Roberts G. D., Galgiani J. N., Bennett J. E., Feingold D. S., Jorgensen J., Kobayashi G. S., Shadomy S. Results of a survey of antifungal susceptibility tests in the United States and interlaboratory comparison of broth dilution testing of flucytosine and amphotericin B. J Clin Microbiol. 1986 Feb;23(2):298–301. doi: 10.1128/jcm.23.2.298-301.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Doern G. V., Tubert T. A., Chapin K., Rinaldi M. G. Effect of medium composition on results of macrobroth dilution antifungal susceptibility testing of yeasts. J Clin Microbiol. 1986 Oct;24(4):507–511. doi: 10.1128/jcm.24.4.507-511.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Drutz D. J. In vitro antifungal susceptibility testing and measurement of levels of antifungal agents in body fluids. Rev Infect Dis. 1987 Mar-Apr;9(2):392–397. doi: 10.1093/clinids/9.2.392. [DOI] [PubMed] [Google Scholar]
  6. Galgiani J. N. Antifungal susceptibility tests. Antimicrob Agents Chemother. 1987 Dec;31(12):1867–1870. doi: 10.1128/aac.31.12.1867. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Galgiani J. N., Reiser J., Brass C., Espinel-Ingroff A., Gordon M. A., Kerkering T. M. Comparison of relative susceptibilities of Candida species to three antifungal agents as determined by unstandardized methods. Antimicrob Agents Chemother. 1987 Sep;31(9):1343–1347. doi: 10.1128/aac.31.9.1343. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Galgiani J. N., Stevens D. A. Antimicrobial susceptibility testing of yeasts: a turbidimetric technique independent of inoculum size. Antimicrob Agents Chemother. 1976 Oct;10(4):721–728. doi: 10.1128/aac.10.4.721. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Galgiant J. N., Stevens D. A. Turbidimetric studies of growth inhibition of yeasts with three drugs: inquiry into inoculum-dependent susceptibility testing, time of onset of drug effect, and implications for current and newer methods. Antimicrob Agents Chemother. 1978 Feb;13(2):249–254. doi: 10.1128/aac.13.2.249. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. LAMPEN J. O., ARNOW P. M., SAFFERMAN R. S. Mechanism of protection by sterols against polyene antibiotics. J Bacteriol. 1960 Aug;80:200–206. doi: 10.1128/jb.80.2.200-206.1960. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Marks M. I., Steer P., Eickhoff T. C. In vitro sensitivity of Torulopsis glabrata to amphotericin B, 5-fluorocytosine, and clotrimazole (Bay 5097). Appl Microbiol. 1971 Jul;22(1):93–95. doi: 10.1128/am.22.1.93-95.1971. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Merz W. G. Candida lusitaniae: frequency of recovery, colonization, infection, and amphotericin B resistance. J Clin Microbiol. 1984 Dec;20(6):1194–1195. doi: 10.1128/jcm.20.6.1194-1195.1984. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Odds F. C. Laboratory evaluation of antifungal agents: a comparative study of five imidazole derivatives of clinical importance. J Antimicrob Chemother. 1980 Nov;6(6):749–761. doi: 10.1093/jac/6.6.749. [DOI] [PubMed] [Google Scholar]
  14. Pfaller M. A., Burmeister L., Bartlett M. S., Rinaldi M. G. Multicenter evaluation of four methods of yeast inoculum preparation. J Clin Microbiol. 1988 Aug;26(8):1437–1441. doi: 10.1128/jcm.26.8.1437-1441.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Polak A., Scholer H. J. Fungistatic activity, uptake and incorporation of 5-fluorocytosine in Candida albicans, as influenced by pyrimidines and purines. I. Reversal experiments. Pathol Microbiol (Basel) 1973;39(2):148–159. doi: 10.1159/000162642. [DOI] [PubMed] [Google Scholar]
  16. Radetsky M., Wheeler R. C., Roe M. H., Todd J. K. Microtiter broth dilution method for yeast susceptibility testing with validation by clinical outcome. J Clin Microbiol. 1986 Oct;24(4):600–606. doi: 10.1128/jcm.24.4.600-606.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Rogers T. E., Galgiani J. N. Activity of fluconazole (UK 49,858) and ketoconazole against Candida albicans in vitro and in vivo. Antimicrob Agents Chemother. 1986 Sep;30(3):418–422. doi: 10.1128/aac.30.3.418. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Ryley J. F., Wilson R. G., Barrett-Bee K. J. Azole resistance in Candida albicans. Sabouraudia. 1984;22(1):53–63. [PubMed] [Google Scholar]
  19. Stevens D. A. Antifungal drug susceptibility testing. A critical review. Mycopathologia. 1984 Sep 30;87(3):135–140. doi: 10.1007/BF00436898. [DOI] [PubMed] [Google Scholar]
  20. Stiller R. L., Bennett J. E., Scholer H. J., Wall M., Polak A., Stevens D. A. Correlation of in vitro susceptibility test results with in vivo response: flucytosine therapy in a systemic candidiasis model. J Infect Dis. 1983 Jun;147(6):1070–1077. doi: 10.1093/infdis/147.6.1070. [DOI] [PubMed] [Google Scholar]

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

RESOURCES