Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get StartedCauses
By Mayo Clinic staffExactly what triggers pemphigus is unknown, but it's an autoimmune disorder.
Normally, your immune system attacks foreign invaders, such as harmful viruses and bacteria. But in pemphigus, your immune system mistakenly produces antibodies that attack healthy cells in your skin and mucous membranes, and more specifically proteins called desmogleins in the majority of cases. Desmogleins bind skin cells to each other. The antibodies binding to the skin cause separation of the cells of the top layer of your skin (epidermis). This separation reaction is known as acantholysis.
Sometimes, pemphigus develops as a side effect from certain medications, such as blood pressure drugs or chelating agents. This type of pemphigus usually disappears when the medicine is stopped.
Paraneoplastic pemphigus is caused by additional antibodies to those seen in other forms of the disorder. It develops in people who have cancer, usually lymphoma or leukemia. In cases in which the cancer hasn't yet been discovered, the appearance of pemphigus blisters may alert doctors to look for a malignancy.