ABSTRACT
BACKGROUND: The cell mediate immunity is of importance for the development of host resistance to dermatophytic infection. OBJECTIVE: The aim of this study was to estimate the clinical usefulness of purified trichophytin and to correlate cell mediate immunity to the clinical parameters of dermatophytosis, i. e. duration of infection, localization of infection and the type of dermatophyte involved. METHODS: For evaluation of cell mediate immunity in dermatophytosis, cutaneous immune reaction was measured in 102 patients with dermatophytosis (75 patients with chronic dermatophytosis and 27 patients with non-chronic dermatophytosis) by means of intradermal injection of purified trichophytin extracted from Trichophyton(T.) mentagrophytes. RESULTS: The results are summarized as follows: Patients with chronic dermatophytosis were positive in 10.7% of cases, while 51.9% of the patients with non-chronic dermatophytosis showed positive delayed cutaneous reactions (p<0.05). Of the dermatophytes isolated, 81.4% of the patients were chronically infected by T. rubrum. Delayed cutaneous reactions occured in infections with T. rubrum in only 17.1% of cases, but this difference was not statistically significant (p=0.06). Of the patients with tinea cruris, delayed cutaneous reactions were registered in 50%, but only in 15.1% those with tinea unguium (p<0.05). The significant difference in the rate of positivity in delayed reactions was not shown between the patients group with nail infection (15.1%) and the patients group without nail infection (28.6%). The rate of positivity in immediate and delayed reactions of the patients group in the multiple lesions (50%, 13.2%, respectively) was higher than that of the patients group in the single lesion (46.9%, 26.6%, respectively). CONCLUSION: The present study reinforced the hypothesis that susceptibility to chronic dermatophytosis is related to a lack of cell mediate immunity to the infectious agents and clinically, purified trichophytin is good for the evaluation of host sensitization to dermatophyte antigens as well as cell mediate immunity in dermatophytosis.