title: Concentric Polycyclic Regrowth Pattern in Alopecia Areata.
abstract: Alopecia areata (AA) is a common form of autoimmune nonscarring hair loss of scalp and/or body. Atypical hair regrowth in AA is considered a rare phenomenon. It includes atypical pattern of hair growth (sudden graying, perinevoid alopecia, Renbok phenomenon, castling phenomenon, and concentric or targetoid regrowth) and atypical dark color hair regrowth. We report a case of AA that resulted in a concentric targetoid hair regrowth and discuss the possible related theories regarding the significance of this phenomenon.
authors.affiliation: Department of Dermatology, Universidade Federal Fluminense, Niterói, Brasil.
authors.forename: Lilian Mathias
authors.initials: LM
authors.lastname: Delorenze
authors.affiliation: Department of Dermatology, Universidade Federal Fluminense, Niterói, Brasil.
authors.forename: Maria Fernanada Reis
authors.initials: MF
authors.lastname: Gavazzoni-Dias
authors.affiliation: Department of Dermatology, Universidade Federal Fluminense, Niterói, Brasil.
authors.forename: Marcelo S
authors.initials: MS
authors.lastname: Teixeira
authors.affiliation: Department of Dermatology, Universidade Federal Fluminense, Niterói, Brasil.
authors.forename: Marcia Kalil
authors.initials: MK
authors.lastname: Aide
keywords: Alopecia areata; corticosteroid treatment; hair disorder; hair regrowth