Blistering Diseases Flashcards
Pemphigus Vulgaris
most common in who?
pts in their 30s and 40s
Pemphigus Vulgaris
associated w/ what meds?
4
- penicillamine
- captopril
- cephalosporins
- phenobarbituals
Pemphigus Vulgaris
generally describe
type of disorder, severity, of what?
life-threatening, chronic autoimmune blistering disorder of the mucus membranes & skin
Pemphigus Vulgaris
pathophys
- type 2 hypersensitivity rxn where autoantibodies against desmoglein lead to acantholysis
- desmoglein connects keratinocytes in the skin
Pemphigus Vulgaris
clinical presentation
- initial: painful erosion/ulceration
- develops: painful, flaccid skin bola that ruptures easily
- leaves painful denuded skin erosions that bleed easily
Pemphigus Vulgaris
where is the initial lesion most commonly located?
intra orally
Pemphigus Vulgaris
what does pos Nikolsky sign mean?
detachment of skin under pressure or trauma
Pemphigus Vulgaris
dx
- punch biopsy
- ELISA- anti-desmoglein or anti-epithelial autoantibodies
Pemphigus Vulgaris
what will you see on punch biopsy?
IgG throughout epidermis
basal keritanocytes in a pattern that resembles a “row of tombstones”
Pemphigus Vulgaris
tx
3 components
- systemic glucocorticoids
- would care
- (+/-) rituximab, mycophenolate, or azathioprine
Bullous Pemphigoid
primariy seen in?
elderly
Bullous Pemphigoid
can be induced by what?
drugs (loop diuretics, metformin)
Bullous Pemphigoid
autoimmune disorder that leads to?
- blister formation
- severe itching
Bullous Pemphigoid
pathophys
- type 2 hypersensitivity rxn
- IgG autoantibodies against hemidesmosomes & basement membrane zone causing subepidermal blistering
Bullous Pemphigoid
clinical presentation
5 components
- Initial: pruritis, eczematous or urticarialerythematous plaques
- progress to: multiple tense large bullae that don’t easily rupture
- mucosal disease (10-30%)
- negative Nikolsky sign
- most commonly found in groin, axilla, trunk, flexural areas of extremities
Bullous Pemphigoid
Dx
- punch biopsy w/ direct immunofluorescence
- ELISA
Bullous Pemphigoid
what do you see on punch biopsy?
- linear C3, IgG along the dermal-epidermal junction, subepidermal blistering, eosinophilia
Bullous Pemphigoid
what do you see on ELISA?
- autoantibodies against BP antigen 230 & 180
Bullous Pemphigoid
tx
localized/mild disease vs extensive/severe
- mild: high potency topical corticosteroids + tetracyclines
- severe: systemic corticosteroids
Porphyria Cutanea Tarda
general overview
hypersensitivity of the skin to abnormal porphyrins when exposed to light, leading to blistering disease of sun exposed areas
Porphyria Cutanea Tarda
caused by which enzyme?
uroporphyrinogen decarboxylase
Porphyria Cutanea Tarda
risk factors
5
- Liver Disease: hepatitis C, alcoholism, hemachromatosis
- Estrogen use
- tobacco use
Porphyria Cutanea Tarda
clinical presentation
- chronic blistering photosensitivity of sun exposed areas
- can lead to hyper or hypo pigmentation or scarring
Porphyria Cutanea Tarda
Dx
- 24 hr collection of urine
- plasma porphyrin profile
Porphyria Cutanea Tarda
tx
treat the underlying cause
