56 - Epidermolysis Bullosa Acquisita Flashcards
EBA is cause by IgG autoantibodies to
Type VII collagen
Common sites of EBA are
Trauma-prone areas
Mode of inheritance of EBA
Sporadic
Both characterized by skin fragility, subepidermal blisters, milia formation and scarring; common of decreased anchoring fibrils
EBA
Hereditary forms of dystrophic EB
Cause of decreases or absent anchoring fibrils is a genetic defect in the
COL7A1 gene
Type VII collagen alpha chain domains
- Noncollagenous 1 (NC-1) domain
- Helical domain
- Noncollagenous 2 (NC-2) domain
Most EBA autoantibodies recognize 4 predominant antigenic epitopes within the _____ domain
NC-1
When compared with BP, EBA patients had a higher presence of
C3b and C5
Clinical presentations of EBA
- Classic presentation
- BP-like presentation
- MMP-like presentation
- Presentation reminiscent of Brunsting-Perry pemphigoid
- Presentation reminiscent of LIGAD or CBDC
Most common presentations of EBA
Classical
BP-like
Noninflammatory bullous disease with an acral distribution that heals with scarring with milia formation
Classical presentation of EBA
Classical presentation of EBA is reminiscent of ______ when mild and of the ______ when it is severe
Porphyria cutanea tarda
Hereditary form of recessive dystrophic EB
Widespread, inflammatory vesiculobullous eruption involving the trunk, central body, and skin folds in addition to the extremities
BP-like presentation
Predominant mucosal involvement with or without similar lesions on the glabrous skin
MMP-like presentation
Chronic, recurrent vesiculobullous eruption localized to the head and neck and characterized by residual scars, subepidermal bullae, IgG deposits at the DEJ, and minimal or no mucosal involvement
Brunsting-Perry pemphigoid-like presentation
Subepidermal bullous eruption, a neutrophilic infiltrate, and linear IgA deposits at the BMZ
IgA bullous dermatosis-like presentation
Although mucosal involvement is frequent and severe in (childhood/adult) EBA, the overall prognosis is more favorable than in (childhood/adult) EBA
Childhood
Adult
Systemic disease most frequently associated with EBA
Inflammatory bowel disease
DIF of PCR vs EBA
Both have IgG and complement deposits at the DEJ
PCT - also demonstrates immune deposits around the dermal blood vessels
EBA IIF substrate
Money or rabbit esophagus or human skin
EBA have immune deposits with the _____ zone of the cutaneous BMZ
Sublamina densa
Salt-split skin: Serum IgG on the epidermal roof
BP
Salt-split skin: Serum IgG on the dermal side
EBA
Bullous SLE
Y/N: EBA usually responds poorly to treatment
Yes
EBA patients are often refractory to high doses of systemic glucocorticoids, azathioprine, methotrexate, and cyclophosphamide, especially when they have the ______ form of the disease
Classic mechanobullous form
Often used as a first-line drug for EBA
Colchicine
Common side effect of colchicine
Diarrhea