Comparative Study of Clinical Response to Topical Minoxidil and Topical Corticosteroids in Alopecia Ariata

Introduction: Alopecia areata (AA) is a chronic worldwide inflammatory disease that involves the hair follicle and sometimes the nails.1,2 The hair follicle is an immunologically privileged organ that is protected from the attack by cytotoxic T – lymphocytes (CTLS) by decreasing major histocompatibility complex (MHC) class I expression.3,4 Current evidence indicates that hair follicle inflammation in alopecia areata is caused by a T- cell mediated autoimmune mechanism occurring in genetically predisposed individuals .1,2 AA is a lymphocyte cell mediated inflammatory form of hair loss with research evidence suggesting an underlying autoimmune etiopathogenesis. The development of hair loss involves aberrant modulation of the hair growth cycle, resulting in dystrophic anagen hair follicles and/or increased frequency of telogen state follicles. Genetic susceptibility to the development of AA involves specific alleles of the HLA║ region though other non-HLA genes are also likely to be involved. Susceptibility to the development of AA may be modified by environmental factors, including exposure to proinflammatory agents and possibly other modulators, including stress and diet. 12 Alopecia areata is an immune mediated form of hair loss that occurs in all ethnic groups , ages , and both sexes , with an estimated life risk of 1.7% among the general population .1,5 Overall ,alopecia areata likely affects males and females equally. 6 In most patients , the onset is within the first decades of life , although alopecia areata can start at any age. 7 The disease prevalence peaks between the second and fourth decades . 9 The significance of genetic factors in alopecia areata is underlined by the high frequency of a positive family history in exaggerated individuals. In most reports , this range from 10% to 20% of cases, but mild cases are often over looked or hidden and the true figure may be larger 8 . In the United States, AA was estimated to occur in 0.1%