Bullous pemphigoid (BP) is the most common autoimmune-blistering disease, clinically characterized by erythematous urticarial plaques, blisters, and intense pruritus, induced by autoantibodies against two proteins of the dermo-epidermal junction, BP180 and BP230. A large number of autoimmune diseases are reported in the literature as BP comorbidities, such as multiple sclerosis, but only a few cases are in association with scleroderma and none in association with both.
We present the case of a 68-year-old woman affected by multiple sclerosis and scleroderma who developed severe bullous pemphigoid with a bullous pemphigoid disease area index of 60 and high titers of anti-BP180 and anti-BP230 autoantibodies by enzyme-linked immunosorbent assays. After 2 months of therapy with both intravenous and oral corticosteroids, the active lesions of bullous pemphigoid were remitted with no relapse.
Autoimmune diseases affecting the skin or organs where BP180 and BP230 are present could trigger an immune response to these antigens through an epitope-spreading phenomenon and, over the years, induce bullous pemphigoid onset.