title: Vellus hair cysts presenting as an atypical acneiform eruption.
abstract: A 32-year-old male patient presented for 8 months an asymptomatic therapy-resistant acneiform eruption on his back and buttocks. Skin examination showed several inflammatory papules, which evolved to hyperpigmentation. At the same distribution non inflammatory papules, which resembled rice grains, were also observed. Light microscopy showed small keratin-filled cysts, with an epithelial multilayered wall, without granular layer. Keratin and some vellus hairs were identified inside the cyst, confirming the diagnosis of vellus hair cysts. Diagnosis of vellus hair cysts should be suspected in cases of multiple papules or therapy-resistant cases of acneiform eruptions.
authors: Universidades Federal e Catolica de Pelotas, Brasil. hiramalmeidajr@hotmail.com
authors: Hiram Larangeira de
authors: HL
authors: Almeida
authors: Lisia
authors: L
authors: Nudelmann
authors: Joice
authors: J
authors: Göebel
authors: Nathália
authors: N
authors: Janovik
authors: Juliana
authors: J
authors: Hein
mesh_terms: D017486:Acneiform Eruptions / Q000473:pathology*; D000328:Adult; D002081:Buttocks; D003937:Diagnosis, Differential; D004814:Epidermal Cyst / Q000473:pathology*; D006201:Hair Diseases / Q000473:pathology*; D006801:Humans; D008297:Male