異位性皮膚炎患犬血清學試驗及體表黴菌之研究

Abstract

異位性皮膚炎是犬隻常見的皮膚疾病，患犬接受環境過敏原的刺激後產生過量免疫球蛋白E (IgE)進而誘發一連串過敏反應。在人類的研究，總血清IgE濃度上升，為一異位性皮膚炎發病的風險因子，同時總血清IgE濃度可做為異位性皮膚炎診斷的指標之ㄧ；此外也發現異位性皮膚炎患者在接受皮黴菌治療後，過敏的嚴重程度較為緩和。此篇論文包含兩個研究，第一篇比較異位性皮膚炎患犬及健康犬隻的總血清IgE濃度、總血清IgE濃度和異位性皮膚炎嚴重程度指數(CDESI)的相關性、抗原特異性IgE相對於皮內測試的敏感性及特異性；第二篇則調查異位性皮膚炎患犬體表皮屑芽孢菌及皮黴菌的分布、比較直接鏡檢法和黴菌培養在診斷皮黴菌症的一致性。第一篇研究結果指出，總血清IgE濃度在規律預防內外寄生蟲的犬隻，可作為初步篩選異位性皮膚炎的診斷指標，同時可評估其嚴重程度，而抗原特異性IgE相較於皮內過敏原測試，可能會低估其誘發過敏原；第二篇研究結果發現，台北地區異位性皮膚炎患犬，皮黴菌症盛行率高於皮屑芽孢菌皮膚炎，而直接鏡檢法相較於黴菌培養在皮黴菌症的診斷，有較高的敏感性。

Atopic dermatitis is a common skin disease in dogs which is sensitized to environmental antigens and produces high level of immunoglobulin E (IgE) antibodies. In human patients, increasing total serum IgE concentrations represents a major empiric risk factor for development of atopic disease and was used as a diagnostic indicator of atopic dermatitis. Furthermore, severity of atopic dermatitis was found to be alleviated with management of dermatophytosis in atopic patients. This thesis includes 2 studies, the first study reported total serum IgE concentrations atopic dogs and dogs free from atopic dermatitis, correlation between total serum IgE concentrations and modified canine atopic dermatitis extent and severity index (CADESI), and sensitivity and specificity of allergen-specific IgE in detecting offending allergens against intradermal skin tests. The second study was to investigate the prevalence of Malassezia spp. and dermatophytes in atopic dogs and concordance between results of direct microscopic examination and fungal culture in diagnosis of dermatophytosis. Results of the first study suggested that total serum IgE concentrations could be a screening test and determine severity of atopic dermatitis in dogs received regular parasitic prophylactics, however the use of allergen-specific IgE tests might under-detect offending allergens. Results of the second study showed that the prevalence of dermatophytosis was higher than Malassezia dermatitis in atopic dogs in Taipei area. Comparing to fungal culture microscopic examination exhibited a higher sensitivity in diagnosis of dermatophytosis.