Plica Neuropathica (Polonica) Secondary to Diffuse Alopecia: A Case Report and Literature Review

This article aimed to report a case of plica neuropathica (polonica) associated with diffuse alopecia, highlighting its diagnostic challenges and key distinguishing features. A 62-year-old female patient with a history of hospitalization presented to our department with a one-month history of increased hair loss and intermittent itching of the scalp. Upon examination, she presented with decreased hair density, pseudoalopecic areas, and the presence of plica neuropathica. Trichoscopy showed vellus hairs, anisotrichosis, yellow dots, and hairs with Pohl-Pinkus constrictions. Based on the percentages of anagen and telogen hairs in the presence of miniaturization in the histopathological study, a diagnosis of androgenetic alopecia with acute telogen effluvium was made. Treatment with topical minoxidil was initiated. The patient is being followed up by our service. Plica neuropathica, also known as plica polonica, is a rare condition characterized by irreversible matting and twisting of hair, resulting in a compact, keratinized, and water-resistant mass. It has been associated with the use of hair care products such as shampoos containing cationic surfactants, certain medications, inadequate hair hygiene, or excessive friction. In the literature, it has been described in association with alopecia areata and trichotillomania, but not with diffuse alopecia. Plica polonica is an infrequent clinical finding, and its occurrence in the context of diffuse alopecia has not been previously documented. This subtype of alopecia is challenging due to the lack of specific clinical signs. This case highlights the importance of considering other causes of alopecia associated with plica neuropathica.