Atypical Congenital Triangular Alopecia (Brauer Nevus): Case Report and Review of Literature in Occipital and Mid-Frontal Localizations

Abstract

Introduction: Brauer nevus, also known as congenital triangular alopecia (CTA) is a localized alopecia that rarely affects the occipital or mid-frontal region. CTA is a localized follicular hypoplasia, commonly misdiagnosed as alopecia areata. Although named congenital, onset in adulthood is possible. Case Presentation: We present a review of literature of eighteen atypical locations, providing 4 new cases to the 9 previously published, with particular attention to trichoscopy and histopathological descriptions in this exceptional presentation forms. Discussion: Occipital and mid-frontal Brauer nevus are unusual findings with very few cases reported so far. Because of its rarity and atypical presentation, it can often lead to a misdiagnosis. A higher incidence in the male sex stands clear in these locations. Detection at birth is slightly more frequent than in the classical CTA. Histopathological and trichoscopy findings do not differ from the classical entity, although white or hypopigmented hairs do not seem to be an item present in the mid-frontal forms.