What characterizes the involvement of lichen planus in mucosal surfaces?

The involvement of lichen planus in mucosal surfaces is primarily characterized by the presence of white, reticulate striae, also known as Wickham's striae. These striae are fine, keratotic lines that create a lace-like pattern on the mucosal surfaces, distinguishing lichen planus from other conditions. This description is particularly evident in the oral cavity, where lichen planus may present with these characteristic white lesions.

Mucosal lichen planus can also lead to discomfort and sometimes erosive lesions, but the hallmark finding is the reticular pattern. Understanding these visual distinctions is crucial for accurate diagnosis and differentiation from other conditions that may affect mucosal areas.