Alopecia Areata and Alopecia Areata Incognita

The document from 2019 describes Alopecia Areata (AA) as a common autoimmune hair loss condition with a lifetime risk of 1.7%, often starting before age 20. It can lead to patchy hair loss or total loss on the scalp and body. AA incognita is a diffuse form with a better prognosis. Diagnosis is mainly clinical, with dermoscopy and biopsy used for confirmation. Treatments include topical and intralesional steroids, with no guaranteed sustained remission. Intralesional steroid injections show effectiveness with a maximum of 20 mg per session over 6 months. Systemic steroids have a 60% effectiveness rate in acute cases but are not ideal for long-term use in children due to side effects. Topical immunotherapy is effective in 50% of children and long-standing cases, while anthralin cream has a 25% success rate for cosmetically acceptable hair regrowth. Phototherapy and laser therapy have questionable long-term effectiveness. Other treatments like oral cyclosporine, methotrexate, and JAK inhibitors show variable results, with JAK inhibitors being promising but still under investigation for long-term use and side effects. Subcutaneous low-dose IL2 improved 80% of longstanding AAU cases, and ruxolitinib cream has been successful for eyebrow regrowth.