Alopecia Areata: An Autoimmune Disease Causing Hair Loss

The document from April 19, 2012, reviews Alopecia Areata, an autoimmune disease causing hair loss, affecting approximately 4.5 million people in the U.S. It occurs across all ages and sexes, with a slight male predominance in the 21 to 30 age group, and is associated with other autoimmune disorders. The disease is caused by a T-cell-mediated attack on the hair follicle, leading to various degrees of hair loss. Diagnosis is usually based on clinical signs, with skin biopsy used in unclear cases. Treatments include immunosuppressive and immune-deviation strategies, but no cure exists and treatment outcomes are often unsatisfactory. Oral prednisolone and high-dose intravenous methylprednisolone have shown some efficacy, but with high relapse rates. Topical treatments like minoxidil are also used. The document also discusses the genetic and immunopathological aspects of the disease, suggesting a role for CD8+ T cells and the collapse of immune privilege in hair follicles. It highlights the potential for future therapies to focus on restoring immune privilege and modulating NKG2D-mediated signaling. The document is a general review and does not mention specific study sizes.