Lichen nitidus at a glance

Lichen nitidus is a relatively rare, chronic skin eruption that is characterized clinically by asymptomatic, flat-topped, skin-colored micropapules (see image below). Lichen nitidus mainly affects children and young adults.

Pathophysiology:
The skin is the primary organ system affected. Mucous membranes and nails also might be involved. Lichen planus can clinically mimic lichen nitidus and can sometimes coexist with lichen nitidus.

Physical:
The primary lesions consist of multiple 1- to 3-mm, sharply demarcated, round or polygonal, flat-topped, skin-colored shiny papules that often appear in groups.
The most common sites of involvement are the trunk, flexor aspects of upper extremities, dorsal aspects of hands (see image below), and genitalia. Infrequently, the lower extremities, palms, soles, face, nails, and mucous membranes may be affected. Nail changes include pitting, ridging, splitting, and linear striations..

Causes:
The cause of lichen nitidus is unknown. Controversy exists regarding the relationship between lichen planus and lichen nitidus.

No therapeutic modality has been rigorously evaluated for the treatment of lichen nitidus because of the rarity, lack of significant symptomatology, and disappearance of this disease within 1 or several years. Reported therapies, mostly from isolated case reports, include topical and systemic steroids, topical tacrolimus, systemic cetirizine, levamisole,etretinate, acitretin, itraconazole, cyclosporine, topical dinitrochlorobenzene, psoralen plus UV-A light, and narrow-band UV-B light.