DISCUSSION
This case is an almost perfect representation of lichen nitidus (LN), in terms of morphology, distribution, and configuration. Close examination of individual lesions revealed that the papules were somewhat planar (ie, flat-topped), giving their surfaces a reflective appearance that the eye interprets as white (particularly contrasted with darker skin).
LN can occur in anyone, but it is most often seen in those with darker skin. It is also frequently seen in children, many of whom are atopic, with dry, sensitive skin that is prone to eczema.
In terms of distribution, LN typically affects the extensor triceps, elbow, and forearms bilaterally. With its flat-topped and shiny appearance, LN is sometimes called "mini-lichen planus"—a condition that can demonstrate similar features. Fortunately, LN is seldom itchy and shares none of the distinct histologic characteristics of lichen planus.
LN is quite unusual, if not rare. It is also idiopathic and nearly always resolves on its own—although this can take months to years.
Emollients help to make the affected skin smoother and less visible. Class 4 steroid creams (eg, triamcinolone 0.05%) can help with itching.
TAKE-HOME LEARNING POINTS
- Lichen nitidus (LN) is a rare idiopathic skin condition manifesting with patches of tiny planar papules; it typically affects the elbow and dorsal forearm.
- LN has no pathologic implications and is asymptomatic and self-limited.
- The lesions of LN have a “lichenoid” appearance—ie, a shiny, flat-topped look similar to that seen with lichen planus.
- Fortunately, LN rarely requires treatment, aside from relief of mild itching.