简介：AbstractIntroduction:Scarring and non-scarring alopecias have rarely been described to occur together in the same patient. Distinguishing these two different types of alopecia is important as treatment and prognosis can be different.Case presentation:Here, we report the first case of simultaneous alopecia areata (AA) and central centrifugal cicatricial alopecia (CCCA) in a 35-year-old woman. New alopecic patches were noted on her frontal and vertex scalp. Biopsy of the frontal scalp revealed miniaturized hair follicles and dense lymphocytic infiltrate surrounding the hair bulbs, consistent with AA; while biopsy of the vertex scalp revealed decreased hair follicles, perifollicular fibroplasia with eccentric atrophy of the follicular epithelium, and premature desquamation of the inner root sheath at the level of the lower isthmus, consistent with CCCA.Discussion:Proposed mechanisms of these two alopecia types occurring together include loss of immune privilege, genetic predisposition, as well as unknown external factors that trigger an autoimmune lymphocytic response. Most recently, the peptidylarginine deiminase type III gene has been implicated in both diseases. Although treatment options can overlap between the two diseases, treatment response can differ and CCCA tends to have a worse prognosis.Conclusion:Awareness of this concomitant presentation of two alopecic types is important for appropriate treatment and prognostication.