Epidermolysis Bullosa Acquisita
Saturday, January 01, 2011
Epidermolysis bullosa acquisita (EBA) is an autoimmune disorder
due to autoantibodies to Type VII collagen. EBA may present as a
noninflammatory bullous lesion with acral distribution that heals
with atrophic scarring (similar to porphyria cutanea tarda). EBA
may also present as an inflammatory bullous disorder clinically
similar to bullous pemphigoid, cicatricial pemphigoid, localized
scarring pemphigoid, or linear IgA disease. Diagnosis is confirmed
by special immunofluorescent studies using salt split skin,
staining of histologic sections demonstrating the blister to
identify laminin at the roof of the blister, or with electron
microscopy. Therapy is generally difficult, and most patients have
a chronic progressive disorder lasting many years. The
aggressiveness of treatment should correlate with the severity of
disease. No universally effective therapy has been found for those
patients with the classic disorder of skin fragility and
- For patients with mild or slowly progressive EBA, topical
management plus colchicines is the initial therapy. More aggressive
treatment may not be indicated, as potential therapies may have
significant side effects.
- Protect the affected area with soft dressings to
- Prescribe antibacterial emollients (bacitracin or
mupirocin ointment) to reduce friction and prevent secondary
- Try intermediate to superpotent topical steroids.
- Colchicine 0.6 mg to 2.0 mg/day may be effective. Treat for at
least 6 months to determine efficacy. Diarrhea is an anticipated
side effect in patients taking higher doses. Dapsone in low doses
may be added in patients who do not completely respond and can not
tolerate the maximum doses above.
- Systemic steroids and standard immunosuppressives
(azathioprine, methotrexate, and cyclophosphamide) are often
ineffective in EBA. Some patients with inflammatory lesions
resembling bullous pemphigoid may respond to these therapies.
- Cyclosporine 5-9 mg/kg/day with or without prednisone may
dramatically improve severe disease and induce a remission. Renal
function must be carefully monitored.
- Extracorporeal photophoresis with or without cyclosporine may
lead to remission after as little as a single treatment. As many as
six or seven treatment cycles may be required.
- High-dose intravenous immunoglobin (IVIG) 400mg/kg/day for 5
days, repeated every 4-6 weeks. The time between treatments may be
extended gradually up to once every 3 months.
Complications and Undesired Consequences
- The major pitfall is not recognizing EBA. Direct
immunofluorescence is essential in the evaluation of most bullous
- Cyclosporin A has many side effects, and its prescription
should be restricted to physicians with experience with this drug.
Nephrotoxicity, dose-dependent elevation of liver function tests,
immunosuppression, gingival hypertrophy, hypertrichosis, and
neurologic side effects have all been reported. Toxic side effects
are dose dependent, and can be reduced by monitoring blood
- Mucous membranes are often severely affected. The appropriate
specialist (ophthalmologist, gastroenterologist, urologist, or
gynecologist) should be consulted when there is significant
involvement of the mucosal surfaces.