Trichostasis spinulosa: itchy follicular papules in young adults.

Trichostasis spinulosa is a common inapparent follicular disorder of retained bundles of vellus hairs. There exist two variants: the classical variant presenting with a non-itching, comedo-like lesion on the face in the elderly, and the pruritic variant presenting with itching, follicular papules located on the limbs in young adults. Here we present the microscopic study of the pruritic variant of trichostasis spinulosa in two patients and provide a review of the literature.