Rhodotorula spp. in Laboratory and Veterinary Clinical Practice: Contamination or an Emerging Problem?

Area of Science:

• Veterinary Mycology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Rhodotorula species are increasingly recognized as opportunistic pathogens in animals.
• Underdiagnosis of Rhodotorula infections can lead to inappropriate therapeutic strategies, particularly in companion animal otitis externa.

Purpose of the Study:

• To provide a comprehensive review of Rhodotorula spp. in veterinary medicine.
• To support laboratory and clinical decision-making regarding diagnosis and treatment.
• To highlight knowledge gaps and future research needs.

Main Methods:

• Literature review synthesizing information on taxonomy, ecology, host risk factors, diagnostics, virulence factors, antifungal susceptibility, and case reports.
• Comparison of diagnostic methods for veterinary practice feasibility.
• Analysis of in vitro antifungal activity.

Main Results:

• Rhodotorula spp. possess various virulence factors, including adhesion, biofilm formation, hydrolytic enzymes, and urease.
• Intrinsic resistance to echinocandins and high azole minimum inhibitory concentrations (MICs) are common.
• Amphotericin B, often combined with flucytosine, shows consistent in vitro activity.

Conclusions:

• Distinguishing Rhodotorula infection from contamination requires careful clinicomicrobiological correlation.
• Standardized susceptibility testing and veterinary breakpoints are needed.
• Further research on biofilm behavior, environmental surveillance, and practical treatment guidelines is essential.