Long-term oral candidosis in rats

Area of Science:

• Oral Microbiology
• Mycology
• Infectious Diseases

Background:

• Candida albicans is an opportunistic fungal pathogen.
• Antibiotic use can disrupt oral microbial balance, predisposing to candidiasis.
• Understanding infection dynamics is crucial for managing oral fungal infections.

Purpose of the Study:

• To investigate Candida albicans carriage and infection rates in rats.
• To assess the impact of continuous oral inoculation after tetracycline treatment.
• To identify specific oral sites prone to candidal infection and host response.

Main Methods:

• Conventionalized SPF rats received initial tetracycline medication.
• Continuous oral inoculation with Candida albicans over 34 weeks.
• Monitoring of carriage rates and histopathological examination of oral tissues.

Main Results:

• 50% of rats harbored Candida albicans orally throughout the study.
• Only 25% showed pseudomycelial penetration of the oral mucosa.
• Infection foci predominantly in less cornified epithelium (gingival margin, cheek, sulcular folds).
• Dorsal tongue showed long-standing infection with tissue damage (papillae loss, hyperplasia).

Conclusions:

• Continuous Candida albicans inoculation leads to high carriage but limited mucosal invasion in this model.
• Specific oral mucosal sites are more susceptible to candidal colonization and damage.
• Long-term candidal infection can cause significant histopathological changes in the oral epithelium and underlying tissues.