Abstract: Objective To determine whether Trichophyton rubrum isolated from different lesions in the same patient is of different strains. Methods DNA was extracted from the isolates, then subjected to a polymerase chain reaction-based typing which analyzed the number of repetitive elements in the non-transcribed spacer region of the ribosomal DNA gene repeats. Results Thirty-six strains of T. rubrum were isolated from 17 patients with fungal infection on multiple sites. All strains could be classified into 10 genotypes. The genotype distribution was unrelated to sites of infection. It happened to 8 of the 17 patients that multiple genotypes were involved in T. rubrum infection on different sites in the same body. Conclusion The study shows that multiple genotypes are involved in T. rubrum infection on different sites in the same patient, suggesting external sources of infection rather than infection from a different site in the same individual.

Key words: Molecular strain typing, Trichophyton, Tinea