Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies
Introduction: Determination of local Candida species susceptibility profiles is imperative in establishing empiric guidelines for candidemia, given the associated high mortality rates. Whilst broth dilution methods (eg. microdilution) are considered the “gold standard” reference technique, they prov...
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Elsevier
2025-03-01
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| Series: | International Journal of Infectious Diseases |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1201971224006052 |
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| author | Mrs Rochelle Charvis Dr Glendee Reynolds Campbell Dr Neil McKnight Mrs. Alrica Bruce-Mowatt |
| author_facet | Mrs Rochelle Charvis Dr Glendee Reynolds Campbell Dr Neil McKnight Mrs. Alrica Bruce-Mowatt |
| author_sort | Mrs Rochelle Charvis |
| collection | DOAJ |
| description | Introduction: Determination of local Candida species susceptibility profiles is imperative in establishing empiric guidelines for candidemia, given the associated high mortality rates. Whilst broth dilution methods (eg. microdilution) are considered the “gold standard” reference technique, they prove time-consuming as routine tests in clinical diagnostic laboratories. Less laborious techniques include the Kirby-Bauer disk diffusion method, which is approved by the CLSI solely for testing azoles and echinocandins. The VITEK® 2 (bioMėrieux, Durham, NC), another alternative, is an automated system that utilizes the microdilution principle which allows for MIC interpretation using CLSI breakpoints. This study aimed to determine the agreement between the VITEK® 2 and the Liofilchem (Waltham, MA) antifungal disk diffusion methods for susceptibility of candidemia species, isolated between March 2020 and February 2021 at The University Hospital of the West Indies. Methods: A retrospective cross-sectional study using a census method to collate relevant data from the Laboratory Information System (LIS) was conducted. The candidemia isolates obtained were identified and speciated using the MALDI-TOF Mass Spectrometry (Bruker MS®, Billerica, MA). Antifungal susceptibility testing was done using Liofilchem Antifungal Multodiscs and the VITEK® 2 automated AST-YS08 cards. Comparative analysis was conducted only on antifungal agents for which CLSI breakpoints existed for both methods. Results: Candida species were isolated from 38 of the 7853 blood culture samples processed during the period (0.5% prevalence). Candida albicans, the most frequently isolated species, accounted for 36.8% (n=14), and non-albicans Candida species accounted for 63.2% (n=24). Susceptibility rates for each antifungal tested using Liofilchem Multodiscs and VITEK® 2 were respectively: Caspofungin; 100% versus 94.7%, Voriconazole; 94.7% versus 97.4% and Fluconazole; 89.5% versus 100%. Discussion: Categorical agreements were excellent for caspofungin, voriconazole and fluconazole. The variability in comparative susceptibilities for fluconazole can be attributed to four of the Candida albicans isolates. Minor discrepancies were detected with one isolate of Candida albicans to voriconazole. The caspofungin susceptibilities of the two Candida dubliniensis isolates, and the fluconazole susceptibilities for the two Candida glabrata isolates, could not be compared between the two methods as the VITEK® 2 did not establish MICs for these isolates. These deficiencies should be considered during the clinical use of these drugs to treat those Candida species. Although amphotericin B and flucytosine were tested with both methods, the lack of CLSI breakpoints for the Kirby-Bauer disk diffusion method did not allow for their inclusion in the comparative analysis. Conclusion: The Liofilchem Antifungal Multodisc can be used as an alternative guide for therapeutic decisions for antifungals approved by CLSI. Caution however should be taken when reporting caspofungin for Candida dubliniensis, fluconazole for Candida glabrata and fluconazole-resistant Candida albicans isolates. |
| format | Article |
| id | doaj-art-9169e29436b843f593eea40c7d013ec7 |
| institution | DOAJ |
| issn | 1201-9712 |
| language | English |
| publishDate | 2025-03-01 |
| publisher | Elsevier |
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| series | International Journal of Infectious Diseases |
| spelling | doaj-art-9169e29436b843f593eea40c7d013ec72025-08-20T02:55:16ZengElsevierInternational Journal of Infectious Diseases1201-97122025-03-0115210753010.1016/j.ijid.2024.107530Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West IndiesMrs Rochelle Charvis0Dr Glendee Reynolds Campbell1Dr Neil McKnight2Mrs. Alrica Bruce-Mowatt3University Of The West IndiesUniversity Of The West IndiesUniversity Of The West IndiesUniversity Of The West IndiesIntroduction: Determination of local Candida species susceptibility profiles is imperative in establishing empiric guidelines for candidemia, given the associated high mortality rates. Whilst broth dilution methods (eg. microdilution) are considered the “gold standard” reference technique, they prove time-consuming as routine tests in clinical diagnostic laboratories. Less laborious techniques include the Kirby-Bauer disk diffusion method, which is approved by the CLSI solely for testing azoles and echinocandins. The VITEK® 2 (bioMėrieux, Durham, NC), another alternative, is an automated system that utilizes the microdilution principle which allows for MIC interpretation using CLSI breakpoints. This study aimed to determine the agreement between the VITEK® 2 and the Liofilchem (Waltham, MA) antifungal disk diffusion methods for susceptibility of candidemia species, isolated between March 2020 and February 2021 at The University Hospital of the West Indies. Methods: A retrospective cross-sectional study using a census method to collate relevant data from the Laboratory Information System (LIS) was conducted. The candidemia isolates obtained were identified and speciated using the MALDI-TOF Mass Spectrometry (Bruker MS®, Billerica, MA). Antifungal susceptibility testing was done using Liofilchem Antifungal Multodiscs and the VITEK® 2 automated AST-YS08 cards. Comparative analysis was conducted only on antifungal agents for which CLSI breakpoints existed for both methods. Results: Candida species were isolated from 38 of the 7853 blood culture samples processed during the period (0.5% prevalence). Candida albicans, the most frequently isolated species, accounted for 36.8% (n=14), and non-albicans Candida species accounted for 63.2% (n=24). Susceptibility rates for each antifungal tested using Liofilchem Multodiscs and VITEK® 2 were respectively: Caspofungin; 100% versus 94.7%, Voriconazole; 94.7% versus 97.4% and Fluconazole; 89.5% versus 100%. Discussion: Categorical agreements were excellent for caspofungin, voriconazole and fluconazole. The variability in comparative susceptibilities for fluconazole can be attributed to four of the Candida albicans isolates. Minor discrepancies were detected with one isolate of Candida albicans to voriconazole. The caspofungin susceptibilities of the two Candida dubliniensis isolates, and the fluconazole susceptibilities for the two Candida glabrata isolates, could not be compared between the two methods as the VITEK® 2 did not establish MICs for these isolates. These deficiencies should be considered during the clinical use of these drugs to treat those Candida species. Although amphotericin B and flucytosine were tested with both methods, the lack of CLSI breakpoints for the Kirby-Bauer disk diffusion method did not allow for their inclusion in the comparative analysis. Conclusion: The Liofilchem Antifungal Multodisc can be used as an alternative guide for therapeutic decisions for antifungals approved by CLSI. Caution however should be taken when reporting caspofungin for Candida dubliniensis, fluconazole for Candida glabrata and fluconazole-resistant Candida albicans isolates.http://www.sciencedirect.com/science/article/pii/S1201971224006052 |
| spellingShingle | Mrs Rochelle Charvis Dr Glendee Reynolds Campbell Dr Neil McKnight Mrs. Alrica Bruce-Mowatt Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies International Journal of Infectious Diseases |
| title | Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies |
| title_full | Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies |
| title_fullStr | Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies |
| title_full_unstemmed | Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies |
| title_short | Comparative Evaluation of Susceptibility Results from the Liofilchem Antifungal Multodiscs and the VITEK® 2 Susceptibility Tests for Candida Species Causing Bloodstream Infections at the University Hospital of the West Indies |
| title_sort | comparative evaluation of susceptibility results from the liofilchem antifungal multodiscs and the vitek r 2 susceptibility tests for candida species causing bloodstream infections at the university hospital of the west indies |
| url | http://www.sciencedirect.com/science/article/pii/S1201971224006052 |
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