الفهرس 
ALOPECIA AREATA
Patthogeniic ffacttorsOnly 14 pages are availabe for public view
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Abstract
Alopecia areata is a disfiguring disease characterized by the sudden loss of hair in rounded or oval shaped single or multiple patches with spontaneous remission, reoccurrence, and exacerbation. AA can develop into more severe forms; AT involves the loss of all scalp hair and AU which means the complete loss of all body hair. The histopathologic features of the AA consist of perifollicular lymhocytic infiltrates around anagen hair follicles, consisting of both CD4+ and intrafollicular infiltrates of CD8+ cells. Because AA is a complex polygenetic disease, current treatments are often ineffective in inducing prolonged remission. Little is known about environmental factors, such as diet, that impact the course of AA. Several interactions between retinoids and immunity exist. Vitamin A deficiency impairs the development of cell-mediated immunity and promotes Th1 responses while delaying
Th2 development. High dietary vitamin A accelerated disease progression and numbers of hair follicles in anagen. Lack of vitamin A resulted in a more severe disease. A few immune factors were also altered by diet, suggesting that retinoids alter AA by regulating both the hair cycle and immune response