lichen nitidus

Lichen nitidus is a chronic inflammatory disease of unknown etiology characterized by 1–2 mm, discrete and uniform, shiny, flat-topped, pale flesh-colored or reddish-brown papules that may appear as hypopigmented against dark skin.

Occasionally, minimal scaling is present or can be induced by rubbing the surface of the papules.

The disease usually affects children and young adults and is painless and usually nonpruritic, although protracted itching may occur in some cases. It is sometimes referred to by dermatologists as "mini lichen planus".

Microscopy

 localized granulomatous lymphohistiocytic infiltrate in an expanded dermal papilla
 thinning of overlying epidermis
 downward extension of the rete ridges at the lateral margin of the infiltrate, producing a typical ’claw clutching a ball’ picture.