Pemphigus Foliaceus

What is it?

In pemphigus foliaceus (PF), the immune system makes antibodies against the "glue" that holds skin cells together. The cells separate, forming pimple-like pustules and crusts. Autoimmune skin diseases are rare in cats, but PF is the most common of them. It usually appears suddenly without a known cause, though in some cases it is drug-induced or follows years of skin disease.

What signs should I watch for?

Look for crusts (scabs) and sores around the eyes, ears, bridge of the nose, footpads, and groin. In cats, the nail beds are often affected, causing crusty, sore feet. PF rarely affects the mouth.

How is it diagnosed and treated?

A skin biopsy, taken with a small punch under local anesthesia or sedation, is needed to confirm PF. Treatment suppresses the immune system, usually starting with corticosteroids such as prednisolone or dexamethasone; cats that do not respond may need other immune-suppressing drugs such as chlorambucil or cyclosporine. Antibiotics or topical treatments may be needed for secondary infection. Your veterinarian will plan regular rechecks.

Can it be prevented, and what's the outlook?

• PF cannot usually be prevented, but if a medication is suspected as a trigger, your veterinarian may stop it.
• Autoimmune skin disease is rarely cured but is often well controlled with appropriate medication.