Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide.
BACKGROUND: Acquired resistance to antifungal agents now supports the introduction of susceptibility testing for species-drug combinations for which this was previously thought unnecessary. For pathogenic yeasts, conventional phenotypic testing needs at least 24 h. Culture on a porous aluminum oxide...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2012-01-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC3306290?pdf=render |
| _version_ | 1818500360169324544 |
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| author | Colin J Ingham Sjoukje Boonstra Suzanne Levels Marit de Lange Jacques F Meis Peter M Schneeberger |
| author_facet | Colin J Ingham Sjoukje Boonstra Suzanne Levels Marit de Lange Jacques F Meis Peter M Schneeberger |
| author_sort | Colin J Ingham |
| collection | DOAJ |
| description | BACKGROUND: Acquired resistance to antifungal agents now supports the introduction of susceptibility testing for species-drug combinations for which this was previously thought unnecessary. For pathogenic yeasts, conventional phenotypic testing needs at least 24 h. Culture on a porous aluminum oxide (PAO) support combined with microscopy offers a route to more rapid results. METHODS: Microcolonies of Candida species grown on PAO were stained with the fluorogenic dyes Fun-1 and Calcofluor White and then imaged by fluorescence microscopy. Images were captured by a charge-coupled device camera and processed by publicly available software. By this method, the growth of yeasts could be detected and quantified within 2 h. Microcolony imaging was then used to assess the susceptibility of the yeasts to amphotericin B, anidulafungin and caspofungin (3.5 h culture), and voriconazole and itraconazole (7 h culture). SIGNIFICANCE: Overall, the results showed good agreement with EUCAST (86.5% agreement; n = 170) and E-test (85.9% agreement; n = 170). The closest agreement to standard tests was found when testing susceptibility to amphotericin B and echinocandins (88.2 to 91.2%) and the least good for the triazoles (79.4 to 82.4%). Furthermore, large datasets on population variation could be rapidly obtained. An analysis of microcolonies revealed subtle effects of antimycotics on resistant strains and below the MIC of sensitive strains, particularly an increase in population heterogeneity and cell density-dependent effects of triazoles. Additionally, the method could be adapted to strain identification via germ tube extension. We suggest PAO culture is a rapid and versatile method that may be usefully adapted to clinical mycology and has research applications. |
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| format | Article |
| id | doaj.art-05e502b808bb41d7a08e24ab67c34bca |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-10T20:41:37Z |
| publishDate | 2012-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-05e502b808bb41d7a08e24ab67c34bca2022-12-22T01:34:20ZengPublic Library of Science (PLoS)PLoS ONE1932-62032012-01-0173e3381810.1371/journal.pone.0033818Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide.Colin J InghamSjoukje BoonstraSuzanne LevelsMarit de LangeJacques F MeisPeter M SchneebergerBACKGROUND: Acquired resistance to antifungal agents now supports the introduction of susceptibility testing for species-drug combinations for which this was previously thought unnecessary. For pathogenic yeasts, conventional phenotypic testing needs at least 24 h. Culture on a porous aluminum oxide (PAO) support combined with microscopy offers a route to more rapid results. METHODS: Microcolonies of Candida species grown on PAO were stained with the fluorogenic dyes Fun-1 and Calcofluor White and then imaged by fluorescence microscopy. Images were captured by a charge-coupled device camera and processed by publicly available software. By this method, the growth of yeasts could be detected and quantified within 2 h. Microcolony imaging was then used to assess the susceptibility of the yeasts to amphotericin B, anidulafungin and caspofungin (3.5 h culture), and voriconazole and itraconazole (7 h culture). SIGNIFICANCE: Overall, the results showed good agreement with EUCAST (86.5% agreement; n = 170) and E-test (85.9% agreement; n = 170). The closest agreement to standard tests was found when testing susceptibility to amphotericin B and echinocandins (88.2 to 91.2%) and the least good for the triazoles (79.4 to 82.4%). Furthermore, large datasets on population variation could be rapidly obtained. An analysis of microcolonies revealed subtle effects of antimycotics on resistant strains and below the MIC of sensitive strains, particularly an increase in population heterogeneity and cell density-dependent effects of triazoles. Additionally, the method could be adapted to strain identification via germ tube extension. We suggest PAO culture is a rapid and versatile method that may be usefully adapted to clinical mycology and has research applications.http://europepmc.org/articles/PMC3306290?pdf=render |
| spellingShingle | Colin J Ingham Sjoukje Boonstra Suzanne Levels Marit de Lange Jacques F Meis Peter M Schneeberger Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. PLoS ONE |
| title | Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. |
| title_full | Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. |
| title_fullStr | Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. |
| title_full_unstemmed | Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. |
| title_short | Rapid susceptibility testing and microcolony analysis of Candida spp. cultured and imaged on porous aluminum oxide. |
| title_sort | rapid susceptibility testing and microcolony analysis of candida spp cultured and imaged on porous aluminum oxide |
| url | http://europepmc.org/articles/PMC3306290?pdf=render |
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