Daroach M, et al. - The intention of the experts was to associate serum vitamin D (Vit.D) levels with severity, pattern, and duration of alopecia areata (AA), and density of vitamin D receptor (VDR) expression over hair follicles in AA patients. An inverse association was disclosed between Vit.D deficiency in AA with disease severity and duration. Reduced VDR expression was found in AA. It exhibited an inverse link with inflammation histologically. However, it did not relate to serum Vit.D levels, severity, pattern, or duration of illness.