[Results of patch tests with mite components in atopic dermatitis patients]

House dust mite lipids were investigated in atopic dermatitis (AD) patients. The analysis showed that eicosapentaenoic acid (EPA) was present at 0.88% in total lipid of Dermatophagoides farinae (Df). In the patch tests with crushed 3 live Dfs, the difference of positive rates between AD patients and controls was statistically significant. In the patch test with secretions from opisthonotal glands of mites, 2% citral contained in both D. pteronyssinus (Dp)s and Dfs showed higher rate of positivity with AD patients than controls without statistically significance. In the patch test with the fatty acids of house dust mites, EPA showed higher rate of positivity with AD patients than controls. There was a statistical significance with 100% (as is) EPA. Histopathological findings by hematoxylin and eosin staining with the skin lesions of AD patients and the positive reactions of patch test with crushed 3 live mites and EPA revealed spongiosis in the epidermis and infiltration of mononuclear cells in the upper dermis. The positive subsets of the mononuclear cells were mostly CD4, HLA-DR and ICAM 1, while CD8 positive cells were rare. Based on these findings, not only mite protein but also mite lipids including secretions from mites should be investigated as mite contact allergens in AD.