Here are two diseases that are easy to confuse: pemphigus vulgaris and bullous pemphigoid. Both diseases are characterized by bullae (big, blister-like skin lesions) and both have “pemphig” in their names (“pemphig-” comes from the Greek pemphix, meaning blister, so that makes sense). So what are the differences between the two?
Here’s the key to differentiating between the two disorders. “Pemphigus” is used in a very specific way (you’d think it would be used to describe any blistering disorder, but not so!). It is used to describe blistering disorders caused by autoantibodies against some part of the epidermis, which lead to disruption of the intercellular junctions (and hence bullae). Pemphigus vulgaris, not surprisingly, is the most common type of pemphigus (“vulgar-” comes from the Latin vulgaris, meaning the general public). It occurs primarily in adults between the ages of 30 and 60, and is characterized by big, flaccid bullae that burst easily (in most patients, you’ll see more ruptured, scab-covered bullae than intact ones). Patients often present first with oral bullae and ulcerations, and later develop bullae on the skin.
In this disease, patients have autoantibodies against desmogleins, which disrupt the connections between the squamous cells of the epidermis and cause very superficial, intraepidermal, fragile bullae. If you do immunofluorescence on the skin, you’ll see a kind of outlining of each individual epidermal cell (because there are autoantibodies bound to the junctions between the cells). Treatment consists of immunosuppressive agents; prognosis is variable, but many patients have a higher than normal mortality rate.
This disease is called pemphigoid rather than pemphigus, because it looks like pemphigus but really isn’t! Pemphigus is characterized by autoantibodies against the connections between epidermal cells. In bullous pemphigoid, patients have autoantibodies – but they are against the basement membrane of the epidermis, not against epidermal cell junctions. This means that the bullae are actually subepidermal, so they are less fragile than those of pemphigus vulgaris (if you see a patient with bullous pemphigoid, you’ll see lots of intact, tense bullae, rather than a bunch of ruptured bullae covered with scabs). The immunofluorescence pattern is correspondingly different – you’ll see just a line at the base of the epidermis (rather than the lace-like outlining of epidermal cells you see in pemphigus vulgaris).
Patients with bullous pemphigoid are generally elderly, and the clinical presentation varies a lot (but usually it doesn’t start in the mouth, like pemphigus vulgaris). It’s a less serious disease, usually, since the bullae often don’t rupture (so there’s less chance of infection and scarring).
So if you can remember that pemphigus is a disease that has intraepidermal antibodies, then you can keep the clinical presentation and immunofluorescence pattern of the two diseases straight.
- Dr.ahmed khaleefa said thanks for your effort
- Anne said Really helpful, thanks so much!
- Kristi Richardson said THANKS!
- Kristine said Thanks, Alexandra. I’m sorry to hear about your husband’s tumor. Thank you for sharing t...
- Alexandra Quinn said My husband had a messenteric Desmoid resected from duodenum this Summer and I agree with all of this...
- huma said thanks a lot,good explanation.
- Ayuba said Thanks. I’m a resident in Haematology and you contributed alot to my understanding of the spec...
- marwa said Many thanks for your effort, this is so helpful
- Dr Dhrubajyoti Halder said It is explained very nicely. Thank you.
- Kristine said Hi Ayuba – The exact interaction between the antiphospholipid antibodies and the components of...
- Mosak said Am a vet student an dis xplaination really makes sense.kudos to you guyz
- ahmed said Thank you