Lichen Nitidus: An Unusual Case in an Adult

An otherwise healthy 4-year-old boy was brought for evaluation of a mildly pruritic rash, which had been present for approximately 8 months. The developmental history of the eruption was equivocal, and the child's mother reported no aggravating or ameliorating factors.

Physical examination revealed hundreds of uniform, pinhead-sized, smooth, cream- to flesh- colored, flat-topped papules, predominantly on the abdomen, chest, and back. The palms, soles, mucosa, and nails were not involved. Drs Eric J. Lewis and Charles E. Crutchfield III of Minneapolis made the diagnosis of lichen nitidus based on this fairly classic presentation; in atypical cases, a skin biopsy may be required to confirm the diagnosis.

Drs Lewis and Crutchfield note that lichen nitidus is a chronic papulosquamous disorder of unknown cause that was first reported in 1907. The majority of cases occur during childhood and in persons of color, particularly African-Americans. No gender predilection has been documented, but some report that the condition may occur slightly more frequently in males.

The sites affected in this patient are common areas of involvement, as are the upper extremities and genitals. However, lesions may occur anywhere on the body. Immunohistochemical examination of the infiltrating cells reveals that lichen nitidus is not a variation of lichen planus, as some might believe.

The clinical course usually is benign and self-limited; the majority of rashes resolve within a few months to a few years. Treatment consists of patient (or parent) education and symptomatic measures. Such measures include the application of topical keratolytic and antipruritic moisturizer/emollients, particularly after bathing. Hydroxyzine hydrochloride and diphenhydramine hydrochloride may be used if the pruritus interferes with sleep.

REFERENCES:
1. Pinkus F. Lichen nitidus. Arch Dermatol Syphilology. 1907;88:11-16.
2. Smoller BR, Flynn TC. Immunohistochemical examination of lichen nitidus suggests that it is not a localized papular variant of lichen planus. J Am Acad Dermatol. 1992;27:232-236.