This rare skin condition causes large, fluid-filled blisters to form on the skin, causing bullous pemphigoid. Bullae are itchy and painful blisters that usually appear on the lower abdomen, groin, inner thighs, armpits, or flexural areas, but can also affect other parts of the body.
As an autoimmune disorder, bullous pemphigoid causes the body’s immune system to mistakenly attack its own healthy tissues, causing the disease. In this case, the immune system produces antibodies that target a protein called BP180, found in the basement membrane, a thin layer of tissue that separates the outer layer of the skin (epidermis) from the deeper layer (dermis). As a result, blisters form on the skin due to inflammation and damage.
The exact cause of bullous pemphigoid is unknown, but some factors that may trigger or worsen the condition include:
Age: Bullous pemphigoid is more common in older adults, especially those over 60 years old.
Medications: Some drugs, such as penicillin, sulfasalazine, furosemide, or NSAIDs, may induce or aggravate bullous pemphigoid.
Other diseases: Some chronic conditions, such as diabetes, thyroid disorders, or cancer, may increase the risk of developing bullous pemphigoid.
Infections: Some viral or bacterial infections, such as herpes simplex, hepatitis C, or Helicobacter pylori, may be associated with bullous pemphigoid.
Ultraviolet light: Exposure to sunlight or artificial UV light may trigger or worsen bullous pemphigoid.
Symptoms of bullous pemphigoid include large, tense, and often irregularly shaped blisters. These blisters may be clear, yellow, or bloody, and they may rupture and ooze fluid. They may also become infected or form scars. They may also cause redness, swelling, or inflammation around them.
The blisters are usually very itchy and can interfere with daily activities and sleep quality. They may also cause pain, burning, and stinging sensations. Some people may also experience fever, fatigue, and weight loss.
In addition to the mucous membranes of the mouth, eyes, nose, throat, or genitals, bullous pemphigoid can also cause ulcers, blisters, or erosions in these areas, causing symptoms such as difficulty swallowing, dry eyes, or genital irritation.
Bullous pemphigoid can be diagnosed by a dermatologist, a doctor who specializes in skin diseases. The diagnosis is based on the following tests:
Physical examination: The doctor will examine the skin and mucous membranes for signs of blisters, inflammation, or infection.
Skin biopsy: The doctor will take a small sample of the affected skin and examine it under a microscope for signs of damage to the basement membrane and the presence of antibodies.
Blood test: The doctor will check the blood for the level of antibodies against BP180 or other proteins involved in bullous pemphigoid.
Immunofluorescence test: The doctor will apply a fluorescent dye to the skin or blood sample and observe it under a special microscope for signs of antibody binding to the basement membrane.
Bullous pemphigoid is a chronic condition that can last for months or years, with periods of remission and relapse. The treatment options include:
Corticosteroids: These are anti-inflammatory drugs that suppress the immune system and reduce antibodies production. They can be applied topically to the skin, taken orally, or injected into the bloodstream. However, if they are used for a long time or in high doses, they can have serious side effects, including weight gain, high blood pressure, diabetes, osteoporosis, or infections.
A drug called an immunosuppressant can also suppress the immune system and reduce antibody production. Especially in cases of bullous pemphigoid that are severe or resistant, they can be used alone or in combination with corticosteroids. The drugs include azathioprine, methotrexate, mycophenolate mofetil, and cyclophosphamide. Additionally, they may cause serious side effects, including liver damage, kidney damage, bone marrow suppression, and an increased risk of infection or cancer.
Among these drugs are rituximab, omalizumab, and intravenous immunoglobulin, which can modify the immune system and reduce inflammation and skin damage. Patients who cannot tolerate corticosteroids or immunosuppressants or who have severe or resistant bullous pemphigoid may benefit from them. Additionally, they may cause serious side effects, including infusion reactions, allergic reactions, and an increased risk of infection or cancer.
A number of antibiotics are used to treat or prevent infections that can occur from blisters or from the use of immunosuppressive drugs. These include tetracycline, doxycycline, and erythromycin. Side effects include nausea, diarrhea, or allergies.
Medications such as diphenhydramine, cetirizine, or fexofenadine are antihistamines that reduce itching and inflammation caused by blisters. They may also have side effects, such as drowsiness, dry mouth, or blurred vision.
Taking care of wounds involves cleaning, dressing, and protecting blisters and the surrounding skin to prevent infection, promote healing, and relieve pain. It may also involve the use of moisturizers, emollients, or topical anesthetics.
There is no known way to prevent bullous pemphigoid, but some measures that may help reduce the risk or severity of the condition include:
Some factors, such as medications, infections, or UV light, may exacerbate bullous pemphigoid. It is advised to avoid or limit exposure to these factors, or consult your physician before taking any new medications.
In order to prevent bullous pemphigoid, it is important to maintain a healthy lifestyle, including following a balanced diet, exercising regularly, and managing existing health conditions.
It is important to seek medical attention as soon as possible if any symptoms or signs of bullous pemphigoid appear, including blisters, itching, or fever. By diagnosing and treating the condition early, complications can be avoided and the prognosis can be improved.
