Pemphigus is derived from the Greek word pemphix meaning bubble or blister. Pemphigus vulgaris (PV) is a rare and potentially fatal autoimmune disease characterized by blisters on the skin and mucous membranes.
Worldwide annual incidence has been estimated at 0·76–6·7 cases per million , with the U.S. being on the low side of that range and countries like Iran and India on the high side.
Pemphigus describes a group of chronic bullous diseases, originally named by Wichman in 1791 . There are several types of pemphigus and other similar blistering disorders. The type of disease depends on where the blisters form.
- Pemphigus vulgaris is the most common type of pemphigus in the United States.
- Pemphigus vegetans is a form of pemphigus with thick sores in the groin and under the arms.
- Pemphigus foliaceus involves sores or blisters on the face, scalp and chest. Unlike pemphigus vulgaris, PF blisters do not form in the mouth.
- IgA pemphigus is characterized by different type of antibody binding to the cell surface of epidermal cells.
- Paraneoplastic pemphigus is distinct from pemphigus but has some similar features. It occurs in people with certain types of cancer.
PV can effect both mucous (mouth) and epidermis (skin), and it normally starts in the mouth and moves to the trunk. It’s very hard to diagnose because (a) it’s so rare and (b) it mimics other skin infections (viral and bacterial).
In Mike’s case, the process of elimination included tests for herpes, HIV and staph.
The blisters result from the body’s immune system attacking the proteins that hold skin cells together. One doctor described it to us like this: visualize a brick wall with the concrete blocks being held together by mortar. In this disease, the body attacks the mortar breaking the wall.
Risk factors
- Age 50-60 is peak onset
- Genetic heritage: Ashkenazi Jews , some Spanish and Iranian/Indian populations
Nitty gritty
- Predisposition to pemphigus is linked to genetic factors. Certain major histocompatibility complex (MHC) class II molecules, in particular alleles of human leukocyte antigen (HLA) DR4, appear to confer susceptibility to pemphigus vulgaris.