<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I have noticed that my ankles, feet, and legs have started swelling up. Do you know what could be causing this?  <response>: Yes, peripheral edema or swelling in the legs, can be a symptom of pemphigus. Pemphigus is an autoimmune disease that causes blistering of the skin and mucous membranes. It can also affect organs like the lungs and kidneys. I will need to do some tests to confirm the diagnosis. 