| • | AKA Bullous disease of the aged >60 years old (“bullous pemphig-old”) |
| • | herpes gestationis, cicatricial pemphigoid = same family, 180kd antigens |
Clinical:
| • | tense blisters, few erosions |
| • | Sometimes bullae are on urticarial skin |
| • | Mucous membranes involvement less common, and less severe and painful (vs. pemphigus vulgaris vs. Stevens-Johnson) |
| • | heal without scar formation |
Histology
| • | hallmark is a subepidermal blister with a normal epidermis and a variable dermal infiltrate composed predominantly of eosinophils |
| • | DIF: linear deposits of IgG and C3 at epidermal basement membrane |
| • | IIF: most patients have circulating IgG anti-BMZ antibodies; no correlation of antibody titer with disease activity (vs. pemphigus vulgaris) |
BPAg1 - intracytoplasmic hemidesmosomal protein (230kd)
BPAg2 - transmembrane hemidesmosomal protein (180kd) mnemonic - You’re 18 years old when you get pregnant and get herpes gestationis which has a 180kd antigen, which is a transmembrane protein (and therefore spans many diseases: BP, HG, and cicatricial pemphigoid)
ddx: cicatricial pemphigoid, herpes gestationis, epidermolysis bullosa acquisita, dermatitis herpetiformis, linear IgA bullous dermatitis
Prognosis - usually self-limited; 5 or 6 years
Treatment:
| • | the newer thinking is "conservative treatment" including high-potency topical steroids (vs. systemic steroids) |
| • | tetracycline 500mg QID / Niacinamide 400 TID |
| • | Kenalog IM 40mg Q 3wks (lengthening intervals) |
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