Bullous pemphigoid
most common form of autoimmune subepidermal blistering disease.
occurs in 0.3% of cancer patients treated with checkpoint inhibitors, antibiotics, penicillamine, potassium iodide, frusemide, captopril, gold, penicillin, sulfasalazine, and topical fluorouracil
looks like:
- Nonspecific rash for several weeks before blisters appear
- Eczematous areas resembling nummular dermatitis
- Urticaria-like red skin
- Annular (ring-shaped) lesions
- Smaller blisters (vesicles)
- Prurigo nodules (pemphigoid nodularis)
- Clear or cloudy, yellowish or bloodstained blister fluid
- Postinflammatory pigmentation
- Milia in healed areas
treatment
- If very widespread, hospital admission may be arranged to dress blisters and erosions.
- Ultrapotent topical steroids to treat limited disease < 10% of body surface (eg, clobetasol propionate cream)
- Systemic steroids (eg, prednisone)
- Tetracycline antibiotics, usually doxycycline 200 mg/day; doxycycline has fewer adverse effects than oral corticosteroids and is effective on its own for mild disease