In which condition might one observe deep, painful, red erosions as a manifestation?

Deep, painful, red erosions are characteristic of lichen planus, particularly when it presents in its erosive form. This condition is an inflammatory dermatosis that can affect the skin and mucous membranes. In the oral cavity, lichen planus may lead to painful erosions that appear as shiny, white lesions surrounded by a reddish halo and are typically painful.

The lesions in lichen planus are not merely superficial; they penetrate deeper into the mucosal tissues, resulting in inflammation and ulceration, which can cause significant discomfort for patients. This is a distinctive feature that helps differentiate it from other skin conditions. While eczema, psoriasis, and herpes infection can also cause skin lesions, they do not typically present with the same combination of features—particularly the deep erosions associated with lichen planus. Eczema generally causes weeping, crusted lesions, psoriasis presents with raised, scaly patches, and herpes infections usually lead to vesicular lesions that eventually ulcerate but do not typically manifest as deep erosive lesions in the same manner as lichen planus.