What distinguishes pemphigus vulgaris from mucous membrane pemphigoid?

Pemphigus vulgaris is characterized by acantholysis, which is the loss of connections between keratinocytes in the epidermis. This leads to the formation of blisters in the skin and oral mucosa. The condition is autoimmune, resulting from the body’s own antibodies targeting desmosomal proteins, specifically desmogleins, leading to the disruption of cell adhesion.

In contrast, mucous membrane pemphigoid is primarily a subepithelial blistering condition that does not typically feature acantholysis. Instead, it involves autoimmune responses against components of the basement membrane, leading to a different clinical presentation and histological findings.

Understanding this distinction is crucial for diagnosing and managing these two similar yet pathologically different conditions. The presence of acantholysis in pemphigus vulgaris specifically helps differentiate it from mucous membrane pemphigoid, where such changes are absent.