Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance

Aziz Utku Önel; Murat Yıldırım

doi:10.33988/auvfd.1695492

Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance

Abstract

The absence of standardized culture media for antifungal susceptibility testing (AFST) of animal dermatophytes leads to considerable challenges in result interpretation and treatment selection. This study aimed to compare the performance of Mueller-Hinton Agar (MHA) and Dermasel Agar (DA) for AFST of feline dermatophytes using disc diffusion and E-test methodologies. Skin and hair samples were collected from cats exhibiting clinical signs of dermatophytosis, including alopecia, erythema, and pruritus. A total of 28 dermatophyte isolates were identified by conventional techniques, of which 26 were identified as Microsporum (M.) canis, and 2 as Nannizzia (N.) gypsea. Antifungal susceptibility to itraconazole, fluconazole, ketoconazole, clotrimazole, posaconazole, and voriconazole was determined using the disc diffusion method on both media. In addition, the E-test method was used to determine the minimum inhibitory concentrations of these antifungal agents. The performance of the media was evaluated according to ISO 11133 standards. Comparison of susceptibility profiles showed that while both M. canis (n=26) and N. gypsea (n=2) were highly susceptible to posaconazole and voriconazole, their efficacy diverged for other agents: itraconazole was effective against M. canis, whereas N. gypsea was more susceptible to clotrimazole. High productivity rates and consistent colony morphology were observed in MHA. Since MHA is a non-selective and nutritionally balanced medium for the AFST of M. canis and N. gypsea, it is preferred over DA. This study provides crucial data to inform reproducible, evidence-based antifungal therapy and to monitor trends in resistance.

Keywords

References

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Details

Primary Language

English

Subjects

Veterinary Bacteriology, Veterinary Mycology, Veterinary Microbiology, Veterinary Diagnosis and Diagnostics

Journal Section

Research Article

Authors

Aziz Utku Önel ^*
0000-0003-4596-7461
Türkiye

Murat Yıldırım
0000-0002-9576-2280
Türkiye

Early Pub Date

April 9, 2026

Publication Date

-

Submission Date

June 4, 2025

Acceptance Date

January 7, 2026

Published in Issue

Year 2026 Number: Advanced Online Publication

DOI

https://doi.org/10.33988/auvfd.1695492

IZ

https://izlik.org/JA53JW38LY

Cite

RIS / Bibtex

APA

Önel, A. U., & Yıldırım, M. (2026). Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance. Ankara Üniversitesi Veteriner Fakültesi Dergisi, Advanced Online Publication. https://doi.org/10.33988/auvfd.1695492

AMA

1.Önel AU, Yıldırım M. Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance. Ankara Univ Vet Fak Derg. 2026;(Advanced Online Publication). doi:10.33988/auvfd.1695492

Chicago

Önel, Aziz Utku, and Murat Yıldırım. 2026. “Impact of Culture Medium on Antifungal Susceptibility Results for Microsporum Canis and Nannizzia Gypsea: A Comparative Study of Disc Diffusion and E-Test Performance”. Ankara Üniversitesi Veteriner Fakültesi Dergisi, no. Advanced Online Publication. https://doi.org/10.33988/auvfd.1695492.

EndNote

Önel AU, Yıldırım M (April 1, 2026) Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance. Ankara Üniversitesi Veteriner Fakültesi Dergisi Advanced Online Publication

IEEE

[1]A. U. Önel and M. Yıldırım, “Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance”, Ankara Univ Vet Fak Derg, no. Advanced Online Publication, Apr. 2026, doi: 10.33988/auvfd.1695492.

ISNAD

Önel, Aziz Utku - Yıldırım, Murat. “Impact of Culture Medium on Antifungal Susceptibility Results for Microsporum Canis and Nannizzia Gypsea: A Comparative Study of Disc Diffusion and E-Test Performance”. Ankara Üniversitesi Veteriner Fakültesi Dergisi. Advanced Online Publication (April 1, 2026). https://doi.org/10.33988/auvfd.1695492.

JAMA

1.Önel AU, Yıldırım M. Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance. Ankara Univ Vet Fak Derg. 2026. doi:10.33988/auvfd.1695492.

MLA

Önel, Aziz Utku, and Murat Yıldırım. “Impact of Culture Medium on Antifungal Susceptibility Results for Microsporum Canis and Nannizzia Gypsea: A Comparative Study of Disc Diffusion and E-Test Performance”. Ankara Üniversitesi Veteriner Fakültesi Dergisi, no. Advanced Online Publication, Apr. 2026, doi:10.33988/auvfd.1695492.

Vancouver

1.Aziz Utku Önel, Murat Yıldırım. Impact of culture medium on antifungal susceptibility results for Microsporum canis and Nannizzia gypsea: A comparative study of disc diffusion and E-test performance. Ankara Univ Vet Fak Derg. 2026 Apr. 1;(Advanced Online Publication). doi:10.33988/auvfd.1695492