Eating a bowl of chili one night, a woman felt a burning pain as if she had bitten the inside of her cheek. Oddly, the pain lingered. The next day, she looked in a mirror and saw what appeared to be several canker sores inside her mouth. She shrugged them off at first, but then more sores appeared. No sooner would some heal than others would form. Within a few weeks, her mouth was filled with a multitude of blisters that were so painful she could barely eat a thing.

Her primary-care doctor, dermatologist and dentist were all completely mystified. Finally her periodontist did some digging and came up with the answer—it was an autoimmune disease called pemphigus. Yet even with a diagnosis, my loved one had to contact numerous dermatologists before finding one who was familiar with the condition and its treatment.

This story is typical of pemphigus patients, since the disorder is uncommon enough that doctors often don’t think to check for it. Yet early diagnosis and treatment are crucial because they make this potentially serious condition much easier to control, according to Neil J. Korman, MD, PhD, a professor of dermatology at Case Western Reserve University School of Medicine who specializes in autoimmune blistering diseases.

What is this weird disease? With pemphigus, the immune system makes antibodies that mistakenly attack the proteins in skin cells that keep adjacent cells adhering to one another. This causes cells to separate from each other—to become “unglued,” so to speak. Fluid collects between the layers of tissue, forming numerous fragile blisters that rupture easily, shearing away the top layer of skin and leaving open sores.

Of the several types of pemphigus, the most common is pemphigus vulgaris, in which blisters usually appear first in the mouth. Later, blisters may erupt in the mucous membranes of the nose, throat, eyes and/or genitals, as well as on the skin.

Pemphigus occurs most frequently in middle-aged adults and seniors and women are at somewhat higher risk than men. The disease can develop in people of any ethnicity, though it is more common in those of Mediterranean, Middle Eastern or Ashkenazi Jewish descent.

Getting help: If you have mouth sores that do not heal, seek out a dermatologist or otolaryngologist (ear, nose and throat doctor) who is familiar with pemphigus. If your primary-care physician cannot provide a referral, check the Web site of the International Pemphigus & Pemphigoid Foundation. Diagnosis is based on a physical exam, biopsy of affected tissue and a blood test that measures antibody levels.

Pemphigus patients of yesteryear often died when their mucous membranes or skin became so severely damaged that life-threatening infection set in. Today, fortunately, the disease can be controlled with one or more medications. Options include corticosteroids (such as prednisone)…oral immunosuppressants such as mycophenolate mofetil (CellCept), which help keep the immune system from attacking healthy tissues…biological therapies such as rituximab (Rituxan), which target the white blood cells that produce antibodies…and antibiotics or other drugs as necessary to combat infection.

Because pemphigus is a chronic condition, patients may need to be on medication for life—yet all these drugs can have side effects, so the goal is to find the lowest effective dose. In some cases, patients achieve remission and can withdraw from medications. But as Dr. Korman cautioned, “A remission is not a cure. The blisters can come back.”

Your doctor also may advise taking supplements to help minimize medication side effects. Typical recommendations include calcium with vitamin D for patients on steroids and probiotics for patients taking antibiotics.

To minimize mouth pain during a flare-up…

• Drink beverages at room temperature (not hot or cold), using a straw so you can guide the liquid away from the sides of your mouth and down your throat.

• Avoid hard foods in favor of soft ones. Cook vegetables until they are tender…dip foods in sauces to soften them…accompany each bite of food with a sip of liquid.

• Keep a list of foods that worsen your pain. For instance, my relative quickly learned to steer clear of spicy foods, Italian salad dressing and anything with cinnamon. Some pemphigus patients report problems with foods containing thiols (such as chives, garlic, leeks, onions and shallots)…isothiocyanates (found in broccoli, cabbage, cauliflower and turnips as well as mustard)…phenols (in bananas, mangoes, potatoes, tomatoes and milk)…or tannins (in ginger, berries, coffee and tea).

• Dental hygiene can be difficult when mouth tissues are sore and fragile, but remember, it’s still important. Rinse your mouth out with water after eating to remove bacteria…and use a small, soft toothbrush to clean your teeth.

• Use over-the-counter anesthetic mouth lozenges as needed to reduce discomfort.

• For some patients, stress worsens symptoms—so consider practicing meditation or some other relaxation technique.