MOLECULAR TYPING OF CANDIDA-ALBICANS IN ORAL CANDIDIASIS - KARYOTYPE EPIDEMIOLOGY WITH HUMAN IMMUNODEFICIENCY VIRUS-SEROPOSITIVE PATIENTS IN COMPARISON WITH THAT WITH HEALTHY CARRIERS

Candida albicans organisms isolated from the oral cavities of healthy carriers (26 individuals) and compromised hosts (40 human immunodefici ency virus [HIV]-seropositive patients, all showing symptomatic oral c andidiasis) were compared by resolving chromosome-sized DNA molecules into electrophoretic karyotypes. Seven- to 10-band electrophoretic pat terns, were obtained, with significant and reproducible differences in the distributions of the DNA bands, Seven distinct classes were ident ified and were designated type a (8 bands), type b (8 bands), type c ( 7 bands), type d (9 bands), type x (10 bands), type y (10 bands), and type z (9 bands), Pour of these (types a to d) were the most represent ative within all of the isolated strains (95.5%), and the other three (types x to z) were observed only once in three HN seropositive indivi duals (4.5%), Only types b and c were isolated from healthy carriers, with the percentage of their isolation being 61.5 and 38.5%, respectiv ely, while all the described karyotypes were isolated from HIV-seropos itive patients, with type b being the most frequent (45%); this was fo llowed by types c (25%), a (15%), and d (7.5%). The prevalence of type b and c karyotypes in HIV-infected individuals, as web as in healthy carriers, suggests that commensal strains in the oral cavities of heal thy individuals may become the prevalent agents of subsequent oral can didiasis in compromised hosts. However, replacement of the original, c ommensal strain, if there is one, cannot be excluded in a compromised host, although strain replacement may be more reasonably hypothesized for types a and d, since only these types were isolated at a relative high percentage from the oral lesions of HIV-infected individuals.