In vitro susceptibility of Aspergillus and Fusarium associated with equine keratitis to new antifungal drugs.
Abstract: To determine minimum inhibitory concentrations (MICs) of four fungal species isolated from horses presented with equine fungal keratitis (EFK) in the southeastern United States to previously untested azole, echinocandin, and carboxamide antifungal drugs. Methods: In vitro assays were performed to determine the susceptibility of Aspergillus flavus, A. fumigatus, Fusarium falciforme, and F. keratoplasticum to five antifungal drugs representing three modes of action. Results: Luliconazole exhibited increased growth inhibition against both Aspergillus and Fusarium compared to commonly used, standard antifungal drugs. MIC values for luliconazole at 0.001-0.002 µg/mL were at least 25-fold lower than all other antifungal drugs tested, including voriconazole. Conclusions: The increased antifungal activity of luliconazole observed in this study warrants further investigation for its potential as an antifungal drug for equine fungal keratitis.
© 2020 American College of Veterinary Ophthalmologists.
Publication Date: 2020-05-16 PubMed ID: 32418311DOI: 10.1111/vop.12774Google Scholar: Lookup
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- Journal Article
Summary
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The paper is a scientific investigation into the susceptibility of certain fungi that are linked to equine eye infection to a new set of antifungal drugs. It indicates that the antifungal drug luliconazole showed remarkable results to inhibit the growth of the fungi.
Objective of the Study:
- The research aimed at testing the effectiveness of certain untried antifungal drugs (azole, echinocandin, and carboxamide types) on four species of fungi: Aspergillus flavus, Aspergillus fumigatus, Fusarium falciforme, and Fusarium keratoplasticum. These fungi were specifically isolated from horses that have been diagnosed with a common equine eye disorder – equine fungal keratitis (EFK).
Methodology:
- In vitro (outside their normal biological context) susceptibility assays were conducted to evaluate the response of these fungi to five different antifungal drugs. These drugs have been selected because of the three distinct modes of action they represent. It is essential in order to understand which action mode is more effective.
Results:
- The drug luliconazole showed the best performance when compared to the other tested antifungal drugs. It successfully inhibited the growth of both Aspergillus and Fusarium species.
- The minimum inhibitory concentrations (MICs) needed for luliconazole to perform were in the range of 0.001-0.002 µg/mL. This indicates a significantly higher potency as this concentration range is at least 25 times lower than for any other drug tested in this study. This certainly includes voriconazole, a commonly used standard antifungal drug for the treatment of this type of fungal infection in horses.
Conclusion:
- Considering the improved performance of luliconazole in inhibiting the growth of the fungi linked to equine fungal keratitis, the study concludes that further investigation into the potential usage of this drug for the treatment of EFK is merited. Its high potency at lower concentrations indicates that it could become an efficient and innovative treatment option for EFK in horses.
Cite This Article
APA
Roberts D, Cotter HVT, Cubeta M, Gilger BC.
(2020).
In vitro susceptibility of Aspergillus and Fusarium associated with equine keratitis to new antifungal drugs.
Vet Ophthalmol, 23(5), 918-922.
https://doi.org/10.1111/vop.12774 Publication
Researcher Affiliations
- Department of Clinical Sciences, North Carolina State University, Raleigh, NC, USA.
- Center for Integrated Fungal Research, North Carolina State University, Raleigh, NC, USA.
- Center for Integrated Fungal Research, North Carolina State University, Raleigh, NC, USA.
- Department of Clinical Sciences, North Carolina State University, Raleigh, NC, USA.
MeSH Terms
- Animals
- Antifungal Agents / pharmacology
- Antifungal Agents / therapeutic use
- Aspergillus / drug effects
- Eye Infections, Fungal / drug therapy
- Eye Infections, Fungal / microbiology
- Eye Infections, Fungal / veterinary
- Female
- Fusarium / drug effects
- Horse Diseases / drug therapy
- Horse Diseases / microbiology
- Horses
- Imidazoles / pharmacology
- Imidazoles / therapeutic use
- Keratitis / drug therapy
- Keratitis / microbiology
- Keratitis / veterinary
- Male
- Microbial Sensitivity Tests
Grant Funding
- Tri-Institutional Molecular Mycology and Pathogenesis Training Program (MMPTP)
References
This article includes 12 references
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Citations
This article has been cited 5 times.- Arimoto S, Inagaki K, Todokoro D, Suzuki T, Makimura K, Ishino T. Antifungal Efficacy of Luliconazole in an Experimental Rabbit Model of Fungal Keratitis Caused by Fusarium solani. Mycopathologia 2023 Aug 21;.
- Foote BC, Smith JS, Bowden AC, Allbaugh RA, Sebbag L. Case Report: Successful Management of Refractory Keratomycosis in an Alpaca Using Penetrating Keratoplasty and Combination Antifungal Therapy (Caspofungin 0.5% and Terbinafine 1%). Front Vet Sci 2021;8:644074.
- Roberts DM, Thomas JE, Salmon JH, Cubeta MA, Stapelmann K, Gilger BC. Cold atmospheric plasma improves antifungal responsiveness of Aspergillus flavus and Fusarium keratoplasticum conidia and mycelia. PLoS One 2025;20(8):e0326940.
- Dieste-Pérez L, Holstege MMC, de Jong JE, Heuvelink AE. Azole resistance in Aspergillus isolates from animals or their direct environment (2013-2023): a systematic review. Front Vet Sci 2025;12:1507997.
- Roberts D, Salmon J, Cubeta MA, Gilger BC. Phase-Dependent Differential In Vitro and Ex Vivo Susceptibility of Aspergillus flavus and Fusarium keratoplasticum to Azole Antifungals. J Fungi (Basel) 2023 Sep 26;9(10).
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