Eruptive vellus hair cysts.
Two children had a hyperpigmented monomorphous papular eruption of several years' duration. Biopsy specimens demonstrated cysts in the middle dermis that contained multiple fragmented vellus hair shafts. The eruption in one child involuted spontaneously. The cause of these lesions is obscure. The term eruptive vellus hair cysts is proposed for this entity.
D001706:Biopsy; D002648:Child; D003560:Cysts / Q000175:diagnosis* / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D005542:Forearm; D006197:Hair / Q000473:pathology; D006801:Humans; D008297:Male; D012867:Skin / Q000473:pathology; D012871:Skin Diseases / Q000175:diagnosis / Q000473:pathology; D013909:Thorax