Pathogenicity of Candida krusei and Candida albicans in the tongue of rats

The aim of the present study was to compare the potential of Candida krusei and C. albicans to colonize and infect the oral mucosa in a conventional r at model. Thirty adult female Sprague-Dawley rats were inoculated orally wi th 0.1 ml of yeast suspension (3.10(8) cfu/ml). After 3 weeks of inoculatio n, all the animals were killed using ether anaesthesia. Histological sectio ns of tongues were stained with PAS and Grocott's staining. Characteristic histological changes of mucosal candidosis were discernible on the lingual mucosa of rats infected with C. albicans and C. krusei including parakerato sis, microabscess formation and polymorph infiltration of the lingual epith elium. Although both species produced fungal hyphae that penetrated the epi thelium, C. albicans hyphae tended to be relatively more profuse. The study indicated the better ability of C. albicans to colonize and infect the ora l mucosa compared with C. krusei. The aetiological role of Candida spp. in the progress of oral mucosal lesions to carcinoma postulated. Therefore, th is animal model can constitute a suitable device for validating this hypoth esis.