Trends in antifungal susceptibility and virulence of Candida spp. from the nasolacrimal duct of horses.

The article is a scientific research study that evaluates the antifungal resistance and production of harmful factors in different types of the Candida species found in the tear ducts of horse population in Ceará, Brazil.

Study Design and Data Collection

• The research adopts a cross-sectional study design to scrutinize the resistance against antifungal treatments and the production of virulence (harm causing) factors in various strains of the Candida species. Candida is a type of fungus that can cause infections in both humans and animals.
• The examination was carried out specifically on fungi isolates from the nasolacrimal duct (the tear duct) of 103 horses in Ceará, Brazil. This region and the specific animal population were chosen based on reasons not provided in the abstract.
• Two types of samples were collected from each horse: one from the outlet of the nasolacrimal duct using sterile cotton swabs and another from the inner part of the duct using a probe to instill saline solution.

Findings on Candida Strains and Resistances

• There were 77 strains of Candida isolated from the collected samples. The most prevalent species among them were: C. famata, C. tropicalis, C. guilliermondii, and C. parapsilosis sensu lato.
• The researchers also found evidence of antifungal resistance among these isolates. Specifically, one strain of C. glabrata was found to be resistant to caspofungin, an antifungal medicine. Moreover, one strain exhibited resistance to only fluconazole (another antifungal drug), and 11 showed resistance to itraconazole (yet another antifungal medication). Notably, eight strains of C. tropicalis were resistant to both fluconazole and itraconazole.

Evidence of Virulence Factors

• The extracted Candida isolates were also evaluated for their capacity to produce harmful enzymes, specifically phospholipases and proteases, both associated with infection establishment and progression.
• It was found that a total of 28 of the isolates had phospholipases and 12 had proteases. This suggests that these Candida strains not only have the ability to resist antifungal treatment, but also to produce enzymes that can increase the severity of an infection and disrupt the normal biological functions of the host – the horses in this case.

Importance of the Findings

• The study poses significance in understanding the trends in antifungal resistance and virulence potential of Candida species from the microbiota (the community of microorganisms) inhabiting the nasolacrimal (tear) duct of horses.
• The findings could be useful to inform treatment strategies for fungal infections in horses, notably in managing antifungal resistance and virulence.