disorder of pilosebaceous unit keratosis trichostasis spinulosa MEDGEN:82669 trichostasis spinulosa icd11.foundation:509265047 UMLS:C0263487 elevated dark spiny papules on the face or trunk MONDO:0043206 SCTID:21049007 MESH:C536558 Trichostasis spinulosa (TS) is a condition where instead of one hair protruding from a hair follicle, a bundle or bush of hair come out of a single follicle. This results in elevated, dark spiny papules on the head, face (usually the nose), and trunk. In this condition, there are numerous tiny open pores filled with multiple tiny short hairs, usually only visible with a magnifying glass. TS usually does not cause problems andmay only be noticed as an incidental finding. The exact cause is unknown.