Causes of alopecia in the setting of SLE
1. Active systemic disease can result in diffuse stress alopecia (telogen effluvium). This type of alopecia can occur about 2 to 4 months after a severe disease flare and cause massive hair shedding. This condition is often reversible once disease activity is controlled.
2. DLE results in patchy hair loss corresponding to the distribution of discoid skin lesions. This hair loss is permanent because the hair follicles are damaged by the inflammation.
3. Drugs such as CYC can result in diffuse hair loss, which is reversible after therapy is discontinued and disease activity decreases.
4. Some SLE patients can have a focal alopecia areata-like presentation with patchy areas of hair loss. This may be due to vasculitis or antibodies directed against hair follicles.