Diagnosis and treatment of alopecia areata

Alopecia areata (AA) is a disease in which the patient experiences a sudden loss of scalp hair leaving round patches. It has a lifetime risk of 1.7%. AA is known to occur on any part of the body, including the scalp, beard area, axilla, and even the pubic area. Although the pathogenesis of AA is poorly understood, the consensus is that AA is an organ-specific autoimmune disease that typically presents in the hair follicles. Susceptibility to the development of AA may be modified by environmental factors, including exposure to pro-inflammatory agents and other modulators. The differentiation of AA can sometimes be challenging as several conditions (such as trichotillomania, tinea capitis, telogen effluvium, and lupus) may resemble AA. Obtaining the patient's history, performing a hair pull test, and skin biopsy or dermoscopic findings can be helpful for confirmation. Treatment for AA is usually based on patient age and the extent of hair loss, but there are no therapeutic agents that are curative or preventive for AA. AA can progress unpredictably. Indicators of poor prognosis include atopy, co-occurring immune diseases, positive family history, young age of onset, and ophiasis.