How do pemphigus vulgaris and pemphigus foliaceus differ?

Pemphigus vulgaris (IgG directed against DSG3 and DSG1) is a chronic blistering disease that typically affects adults and usually begins in the oral mucosa. Flaccid vesicles and bullae develop on the face, scalp, neck, chest, groin, and intertriginous areas. These are often tender rather than pruritic. Generalized involvement may occur, and pemphigus vulgaris may be life-threatening. Pemphigus foliaceus (IgG directed against DSG1 only) is a more superficial form of pemphigus and is generally not as severe as the vulgaris type. Patients develop very superficial vesicles and bullae, typically on the scalp, face, upper chest, and back. Because the blisters are very superficial, they often rupture, and secondary changes of scale, crust, and erosions may be the only findings present. For both varieties, the diagnosis is made by routine histologic exam of an early blister, as well as by direct immunofluorescence of perilesional skin and indirect immunofluorescence of patient serum.