1887

Abstract

The progressive increase of invasive disease and reports of resistance among species emphasizes the need for reproducible antifungal susceptibility testing. Inoculum standardization is a crucial step in such procedures. The objective of this study was to develop a fast and precise method of evaluating the cell density of an spore suspension, as an alternative to spectrometric readings or cell-counting with a haemocytometer. Densimat (bioMérieux) is a portable photometer that shows a good correlation with spectrometric readings and can advantageously replace the cumbersome, time-consuming method of cell-counting. Thus, Densimat brings significant improvement to the reproducibility and feasibility of standardization of a fungal inoculum.

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2004-08-01
2019-11-12
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References

  1. Araujo, R. & Rodrigues, A. ( 2004;). Variability of germinative potential among pathogenic species of Aspergillus. J Clin Microbiol (in press).
  2. Bouchara, J.-P., Sanchez, M., Chevailler, A., Marot-Leblond, A., Lissitzky, J.-C., Tronchin, G. & Chabasse, D. ( 1997;). Sialic acid-dependent recognition of laminin and fibrinogen by Aspergillus fumigatus conidia. Infect Immun 65, 2717–2724.
    [Google Scholar]
  3. Bradford Hill, A. ( 1991;). The Wilcoxon signed rank test. In Principles of Medical Statistics, 12th edn, pp. 126–127. Edited by A. Bradford Hill. London: Edward Arnold.
  4. Denning, D. W., Venkateswarlu, K., Oakley, K. L., Anderson, M. J., Manning, N. J., Stevens, D. A., Warnock, D. W. & Kelly, S. L. ( 1997;). Itraconazole resistance in Aspergillus fumigatus. Antimicrob Agents Chemother 41, 1364–1368.
    [Google Scholar]
  5. Espinel-Ingroff, A. ( 2001a;). Germinated and nongerminated conidial suspensions for testing of susceptibilities of Aspergillus spp.to amphotericin B, itraconazole, posaconazole, ravuconazole, and voriconazole. Antimicrob Agents Chemother 45, 605–607.[CrossRef]
    [Google Scholar]
  6. Espinel-Ingroff, A. ( 2001b;). Comparison of the E-test with the NCCLS M38-P method for antifungal susceptibility testing of common and emerging pathogenic filamentous fungi. J Clin Microbiol 39, 1360–1367.[CrossRef]
    [Google Scholar]
  7. Espinel-Ingroff, A. & Kerkering, T. M. ( 1991;). Spectrophotometric method of inoculum preparation for the in vitro susceptibility testing of filamentous fungi. J Clin Microbiol 29, 393–394.
    [Google Scholar]
  8. Espinel-Ingroff, A., Dawson, K., Pfaller, M. & 8 other authors ( 1995;). Comparative and collaborative evaluation of standardization of antifungal susceptibility testing for filamentous fungi. Antimicrob Agents Chemother 39, 314–319.[CrossRef]
    [Google Scholar]
  9. Espinel-Ingroff, A., Bartlett, M., Chaturvedi, V., Ghannoum, M., Hazen, K. C., Pfaller, M. A., Rinaldi, M. & Walsh, T. J. ( 2001;). Optimal susceptibility testing conditions for detection of azole resistance in Aspergillus spp.: NCCLS collaborative evaluation. Antimicrob Agents Chemother 45, 1828–1835.[CrossRef]
    [Google Scholar]
  10. Fridkin, S. K. & Jarvis, W. R. ( 1996;). Epidemiology of nosocomial fungal infections. Clin Microbiol Rev 9, 499–511.
    [Google Scholar]
  11. Gehrt, A., Peter, J., Pizzo, P. A. & Walsh, T. J. ( 1995;). Effect of increasing inoculum sizes of pathogenic filamentous fungi on MICs of antifungal agents by broth microdilution method. J Clin Microbiol 33, 1302–1307.
    [Google Scholar]
  12. Manavathu, E. K., Cutright, J. & Chandrasekar, P. H. ( 1999;). Comparative study of susceptibilities of germinated and ungerminated conidia of Aspergillus fumigatus to various antifungal agents. J Clin Microbiol 37, 858–861.
    [Google Scholar]
  13. Mosquera, J. & Denning, D. W. ( 2002;). Azole cross-resistance in Aspergillus fumigatus. Antimicrob Agents Chemother 46, 556–557.[CrossRef]
    [Google Scholar]
  14. NCCLS ( 2002;). Reference Method for Broth Dilution Antifungal Susceptibility Testing of Conidium-Forming Filamentous Fungi: Proposed Standards. NCCLS document M38-A. Wayne, PA: National Committee for Clinical Laboratory Standards.
  15. Petrikkou, E., Rodríguez-Tudela, J. L., Cuenca-Estrella, M., Gómez, A., Molleja, A. & Mellado, E. ( 2001;). Inoculum standardization for antifungal susceptibility testing of filamentous fungi pathogenic for humans. J Clin Microbiol 39, 1345–1347.[CrossRef]
    [Google Scholar]
  16. Rodríguez-Tudela, J. L., Cuenca-Estrella, M., Díaz-Guerra, T. M. & Mellado, E. ( 2001;). Standardization of antifungal susceptibility variables for a semiautomated methodology. J Clin Microbiol 39, 2513–2517.[CrossRef]
    [Google Scholar]
  17. Štaudohar, M., Benccina, M., van de Vondervoort, P. J. I., Panneman, H., Legiša, M., Visser, J. & Ruijter, G. J. G. ( 2002;). Cyclic AMP-dependent protein kinase is involved in morphogenesis of Aspergillus niger. Microbiology 148, 2635–2645.
    [Google Scholar]
  18. Wasylnka, J. A. & Moore, M. M. ( 2002;). Uptake of Aspergillus fumigatus conidia by phagocytic and nonphagocytic cells in vitro: quantitation using strains expressing green fluorescent protein. Infect Immun 70, 3156–3163.[CrossRef]
    [Google Scholar]
  19. Wasylnka, J. A., Simmer, M. I. & Moore, M. M. ( 2001;). Differences in sialic acid density in pathogenic and non-pathogenic Aspergillus species. Microbiology 147, 869–877.
    [Google Scholar]
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