Pemphigus vulgaris

An autoimmune blistering disease that usually starts in the mouth. Before steroids it was almost always fatal; now it is treatable, and often diagnosed late.

What it is

A rare autoimmune disease in which antibodies attack the connections between skin cells, so the skin and mucous membranes separate and blister.

It differs from bullous pemphigoid, which is commoner, affects older people, and produces tense blisters. In pemphigus the split is higher in the skin, so blisters are flaccid, break easily, and leave raw painful erosions.

**It usually starts in the mouth**, with painful erosions that are frequently diagnosed as recurrent aphthous ulcers, lichen planus or oral thrush for months before the skin becomes involved. Mouth ulcers that persist for weeks, are widespread, and do not respond to usual treatment, deserve a specialist opinion and a biopsy.

It affects the eyes, nose, throat, oesophagus and genitals as well.

Before corticosteroids it was fatal in the great majority. It is now treated with steroids and immunosuppression, and rituximab has become a first-line treatment that produces long remissions and reduces the steroid burden considerably.

Deaths now come mainly from infection and the complications of treatment rather than the disease itself, which shapes what needs watching.

Signs you might notice

Painful mouth erosions, often the first and sometimes the only feature for months.

Difficulty eating, drinking and swallowing.

Flaccid blisters on the skin that break easily, leaving raw painful areas.

Skin that shears off with gentle sideways pressure.

Erosions that crust and heal slowly, usually without scarring.

Involvement of the eyes, nose, throat and genitals.

Urgent: widespread skin loss; inability to eat or drink; fever and signs of infection; or rapidly spreading disease. Extensive skin loss causes fluid and protein loss and infection, like a burn.

Any mouth ulceration lasting more than three weeks, or widespread and not responding to treatment, needs specialist assessment and biopsy.

How it can affect day-to-day life

Mouth pain dominates and stops people eating. Soft, cool, bland food, adequate analgesia including topical treatments, and early dietetic input are all necessary rather than optional. Weight loss is common.

Mouth care is difficult and essential: soft brush, SLS-free toothpaste, bland rinses, and treating secondary thrush, which is common on steroids.

The treatment burden is substantial: long steroid courses with all their effects, plus immunosuppression with infection risk, bone protection, blood sugar and blood pressure monitoring. See Cushing's syndrome.

Infection is the main cause of serious harm now, so fever needs urgent attention, and vaccinations should be up to date before immunosuppression starts, avoiding live vaccines afterwards.

Wound care for eroded areas needs non-adherent dressings and gentle handling; skin should not be rubbed or taped.

It is rare enough that local teams may have little experience, and referral to a specialist immunobullous service is worth asking for.

Supporting someone well

Ask for a biopsy for mouth ulceration that persists for weeks and does not respond to usual treatment.

Ask for referral to a specialist immunobullous or oral medicine service.

Ask about rituximab; it is now first-line and reduces long-term steroid exposure.

Treat mouth pain properly, and get a dietitian involved early.

Use a soft brush, SLS-free toothpaste and bland mouth rinses, and treat thrush.

Get vaccinations up to date before immunosuppression, and avoid live vaccines afterwards.

Treat fever as urgent while immunosuppressed.

Handle skin gently: non-adherent dressings, no tape on fragile skin, no rubbing.

Ask about bone, stomach and glucose protection with long steroid courses.

Where to get help

A GP practice or dentist for referral; dermatology or oral medicine for diagnosis and treatment.

A specialist immunobullous service for management.

Urgent care for widespread skin loss, inability to eat or drink, or fever.

British Association of Dermatologists publish a patient leaflet on pemphigus.