Anti-p200 Pemphigoid

Anti-p200 pemphigoid is a rare subepidermal blistering disease first described in 1996. IgG and/or C3 can be detected by direct immunofluorescence microscopy (IF) at the basal membrane zone of the patient’s skin. Circulating antibodies bind to the blister floor of human salt-split skin in indirect IF and, characteristically, recognize a 200 kDa protein by immunoblotting with dermal extract. About 90% of anti-p200 pemphigoid patients have antibodies against laminin γ1 in addition. Clinically, the disease mimics bullous pemphigoid with tense blisters and erosions on the trunk and extremities as well as intense pruritus. In about 40% of patients, mucous membranes are also affected with oral (in 30% of patients), anogenital (in 10%), and conjunctival lesions (in 2%). Cutaneous lesions may heal with hyperpigmentations but without scarring. In some cases, milia are formed. Treatment is based on topical corticosteroids as well as oral prednisolone and immunomodulating drugs like dapsone and doxycycline.