AA （Alopecia areata） is the most frequent cause of inflammation-induced hair loss, affecting 0.1 to 0.2% of population worldwide. The development of organ-specific autoimmune reactions directed against anagen hair f...AA （Alopecia areata） is the most frequent cause of inflammation-induced hair loss, affecting 0.1 to 0.2% of population worldwide. The development of organ-specific autoimmune reactions directed against anagen hair follicles seems to play a key role in the pathogenesis of alopecia areata. However, the triggering antigen（s） responsible for inducing autoimmune phenomena in these individuals remain unknown. Viral, bacterial or fungal pathogens have been implied as possible triggering factors of autoimmune reactions. The present study aims to identify the role of dematiaceous fungi in the pathogenesis of alopecia areata. 30 patients diagnosed clinically as alopecia areata and 30 normal age matched persons have undergone mycological examination. Mycology examination of the epidermal scrapings was done by DME （direct microscopic examination）, culture on SDA （sabouraud＇s dextrose agar） and imaging. There is significantly higher percentage of positive results for Alternaria species by culture on sabouraud＇s agar in patients group （20%） compared to controls （13.3%） P-value 〈 0.05. The possible role of Alternaria antigens （e.g. antigens involved in melanin synthesis） in triggering autoimmunity in alopecia areata still needs further research on a wider scale of cases.展开更多
文摘AA （Alopecia areata） is the most frequent cause of inflammation-induced hair loss, affecting 0.1 to 0.2% of population worldwide. The development of organ-specific autoimmune reactions directed against anagen hair follicles seems to play a key role in the pathogenesis of alopecia areata. However, the triggering antigen（s） responsible for inducing autoimmune phenomena in these individuals remain unknown. Viral, bacterial or fungal pathogens have been implied as possible triggering factors of autoimmune reactions. The present study aims to identify the role of dematiaceous fungi in the pathogenesis of alopecia areata. 30 patients diagnosed clinically as alopecia areata and 30 normal age matched persons have undergone mycological examination. Mycology examination of the epidermal scrapings was done by DME （direct microscopic examination）, culture on SDA （sabouraud＇s dextrose agar） and imaging. There is significantly higher percentage of positive results for Alternaria species by culture on sabouraud＇s agar in patients group （20%） compared to controls （13.3%） P-value 〈 0.05. The possible role of Alternaria antigens （e.g. antigens involved in melanin synthesis） in triggering autoimmunity in alopecia areata still needs further research on a wider scale of cases.
