Bullous pemphigoid (BP) is the most common form of autoimmune bullous dermatosis.
It has an estimated prevalence of 1/40,000 (and an annual incidence of 1/150,000 cases in France and Germany).
It affects primarily the elderly but it has also been described in children. The disease is characterized clinically by tight, often large, bullae with a clear content, developing primarily on the edge of erythematous plaques. Intense itching is common. The infantile form occurs within the first year after birth and presents as bullous lesions on erythematous skin or on normal acral skin.
The disease is immunologically characterized by the existence of autoantibodies directed against two structural proteins found in the hemidesmosomes of the dermal-epidermal junction. These proteins, called BP antigen 1 (BPAG1 or AgBP230), and BP antigen 2 (BPAG2, AgBP180 or collagen XVII) have respective molecular masses of 230 and 180 kDa.
Very rare familial cases have been reported.
Systemic corticotherapy (prednisone: 1 mg/kg/day) is often referred to as the standard treatment, but the treatment of choice for localized, pauci-bullous and/or minimally evolving forms is topical corticotherapy with class I dermocorticoides.
In some cases, the prognosis for BP patients is poor.
Last update: May 2006