Pemphigus foliaceus (PF)

Pemphigus foliaceus affects the skin. The immune system produces IgG antibodies, largely IgG4, against desmoglein 1, a protein that holds together cells in the upper layers of the epidermis, and T cells specific to desmoglein 1 are found in most people with the condition. Because desmoglein 1 sits closer to the skin's surface and desmoglein 3 remains intact in the deeper mucosal layers, blistering in pemphigus foliaceus stays superficial and the mouth is typically spared, unlike pemphigus vulgaris.

The exact trigger is not well understood, and research describes a mix of genetic susceptibility, environmental exposures, and immune dysregulation behind its development. Pemphigus foliaceus is rare, and an endemic form called fogo selvagem occurs in specific regions of Brazil and other parts of Latin America, where environmental factors are believed to play a larger role.

Common signs

Scaly, crusted, flaky patches and shallow erosions, most often on the scalp, face, chest, and upper back. The blisters are so superficial that they often break before they are noticed, leaving crusting and scale, and the areas can burn, itch, or feel sore.

This is a plain-language summary for orientation, not a diagnosis. Mechanisms are described as current understanding, not settled fact. Work with your own clinician for your care.