Bullous Pemphigoid
This page covers the following:
Introduction
Bullous Pemphigoid (BP) is a rare blistering disorder that usually affects people of age 70 years and over. Blisters appear on the skin and, less often, inside the mouth. BP often starts with a red, itchy rash that looks a bit like eczema or hives and the itchiness can be very irritating. It can remain in that form, but usually will evolve into large painful blisters up to 5cm in diameter and filled with clear fluid, and sometimes blood. Blisters last a few days breaking open, leaving raw patches which heal without leaving a scar, but a cycle may develop in which more form.
How is bullous pemphigoid diagnosed?
The look of the rash, especially if blisters have formed, may be enough for your GP to make the diagnosis, but further investigations are usually performed including a blood test and skin biopsies (under local anaesthetic). This will determine which type of PEM (if any) is present. If BP is suspected, a skin biopsy is performed for histology and direct immunofluorescence testing. Samples from within and around the lesion are often used for histology, but samples of uninvolved skin (often about 3 mm from the edge of a lesion) are used for direct immunofluorescence. Biopsies reveal the layers of skin that are affected by the blisters and direct immunofluorescence shows where the pemphigoid antibodies are binding in the skin. A blood test usually shows the circulating autoantibodies specific to BP.
What are the symptoms of bullous pemphigoid?
The rash and blisters are usually seen on the upper arms and thighs, sometimes spreading to body folds, the abdomen (tummy) and hands and feet. They can, however, appear all over the body depending on the severity. BP can also cause blistering in the mouth but this is rarer. If other mucous membranes are affected then tests for Mucous Membrane Pemphigoid (MMP) should be carried out. Intense itching is also a symptom: see our page on managing itching.
Blisters are firm and filled with a fluid. Most commonly, the fluid is clear but, in some people, it can be bloodstained. The blisters will gradually grow as they fill with fluid and then burst, often leaving raw skin which is very sore. When the skin blisters heal, they do not leave permanent scarring but skin colour changes might be observed after the inflammation has settled down.
Can bullous pemphigoid be cured?
BP cannot be cured but with the right treatment it can be well controlled. However, sometimes it does spontaneously resolve itself after one to five years.
How is bullous pemphigoid treated?
Treatment is with various medications, discussed on the treatment page, as well as aspiration and dressing of large blisters. This should be done very carefully by someone to ensure no infection is introduced. Steroids usually play a big part in treating BP. Steroids can be very effective but may have serious side effects, and these side effects can be more severe in the elderly. Therefore, the lowest possible dose of medicine is used to control the condition to reduce the risk of any side effects. There has been research recently into the treatment of BP that suggests that Doxycycline (an antibiotic) can be an effective and less risky treatment than steroids. Topical steroids are also a less harmful treatment when the disease isn’t too serious.
Where can I find out more information about bullous pemphigoid?
For more detailed information on BP, see the British Association of Dermatologists Patient Leaflet. The New Zealand Dermatology service, DermNet NZ, also produces very good literature on BP.
The UK Centre of Evidence Based Dermatology investigates aspects of BP. You can find videos and information about their findings on their website.
A European Group (European Reference Network - Skin) has developed guidelines for the diagnosis and treatment of some of the autoimmune diseases. The BP guidelines for France, who treat their BP patients differently to the UK, are already published and PEM Friends is helping to develop the same materials for the UK. This is the French version (in English). Also see our Patient Journeys page for more links.