Immunologic Susceptibility to Chronic Dermatophytosis

Abstract

Subjects extensively and chronically infected with dermatophytes were shown to be atopic by demonstration of multiple immediate skin test sensitivities and elevated levels of serum IgE. Three atopic men with no evidence of prior dermatophyte infection were experimentally infected (forearm) with<i>Trichophyton mentagrophytes</i>var<i>granulare</i>. All of the subjects developed cell-mediated immunity (CMI). In two of the subjects, the infections healed spontaneously. In the third subject, who, in addition, developed type I humoral immunity (T-I-HI), the infection did not heal and it spread to his feet. A local antagonism between T-I-HI and CMI was demonstrated. Chronic dermatophytosis develops in most individuals due to immunologic factors, including a local functional, if not actual, defect in CMI. Atopic individuals are predisposed to chronic dermatophytosis because of T-I-HI antagonism of CMI, and the rapid development of CMI tolerance.