Pemphigus vulgaris (PV) is an acquired autoimmune bullous disease of the skin and mucous membranes. It is characterized by the presence of circulating immunoglobulin G (IgG) autoantibodies against desmoglein (Dsg), a keratinocyte cell surface molecule, leading to dysfunction in cell adhesion between keratinocytes. The target antigens in PV are Dsg1 and Dsg3. In the mucocutaneous type, autoantibodies against Dsg1 and Dsg3 are present, whereas the mucosal-dominant type of PV is characterized by autoantibodies against Dsg3.

PV typically affects adults, with a mean age of onset in the fifth and sixth decades of life. Variants of the ST18 gene have been found to confer increased risk of PV in some populations.

Childhood PV, which refers to disease in children younger than 12 years, and juvenile PV, which refers to disease in adolescents aged 13-18 years, are rare, comprising less than 5% of all cases. The mucocutaneous type is more frequently observed in children and adolescents.

PV is characterized by painful erosions on the oral mucosa and flaccid bullae and erosions on the skin. Severe cases of PV can be life-threatening, and complications can be related to immunosuppression from drugs used to treat severe PV, secondary infections, loss of the skin barrier, and poor oral intake.