[Fungi and atopic dermatitis]

Abstract

Attention has recently been centered on fungi as aggravating factors of atopic dermatitis (AD) due to the frequent detection of IgE antibodies to fungi in patients with severe AD and to positive response of some cases of AD to antifungal therapy. Malassezia sp.: In AD patients with prominent symptoms in the head and neck, areas prone to colonization by Malassezia, the titers of specific anti-Malassezia IgE antibodies are high, which positively correlate with the total IgE value and the severity of AD. The patch test against Malassezia antigens is positive. The rate of isolation of Malassezia from the skin of AD patients is higher than that from the skin of healthy control subjects. Candida sp.: In patients with severe AD, the rate of positive skin prick tests for Candida is high, and a correlation exists between positive skin prick test results and the presence of Candida albicans in nasopharynx. However, the reactivity to Candida antigens in the patch tests is reduced, and a negative correlation is seen. There is no difference between the isolation rate of C. albicans from patients with adult-type AD and normal controls. However, AD patients give a significantly greater number of separate colonies. The range of efficacy rate of antifungal therapy of AD is reported to be 50-65 %. The efficacy rate of our own trial falls within this range. Following treatment, the rate of isolation of fungi decrease significantly, and the titers of specific antifungal IgE antibodies are not statistically significant. The clearance of fungi from the tissue following antifungal therapy probably results in the suppression of direct or indirect inflammatory reaction caused by the fungi. We therefore consider antifungal therapy as one of the second-line therapies to be administered in AD cases resistant to conventional basic therapy.