Plica Neuropathica in Two Hispanic Patients

The document describes two cases of Plica neuropathica (PN), a rare condition resulting in tangled hair masses, in a 50-year-old woman with a history of contact dermatitis and a 46-year-old woman who used various hair products. PN is characterized by a hard keratin cement binding the hair, leading to a matted and dirty appearance, and is associated with non-scarring alopecia. The condition's pathogenesis is unclear but may involve physical and chemical damage to the hair shaft, with risk factors including self-neglect, hair felting, substance use, religious practices, chemotherapy, immunosuppressive drugs, infections, and contact dermatitis. Diagnosis can be aided by trichoscopy, which reveals specific hair shaft abnormalities. Treatment typically requires cutting the affected hair, with manual separation possibly helping in early stages.