DERM - Vesicular lesions of the skin Flashcards
top to bottom, what are the layers of the skin?
- corneum
- granulosum
- spinosum
- basal
- basement membrane
the basement membrane is held onto the epidermis by what proteins?
- BPAG1
- BPAG2
loss of what proteins leads to a subepidermal blister?
- BPAG1
- BPAG2
loss of BPAG1 and BPAG2 lead to what type of lesion?
subepidermal blister
blisters can be in what layers?
- subcorneal
- intraepidermal
- subepidermal
bullous pemphigoid consists of blisters in what layer?
subepidermal
what are the cell poor blisters?
- porphyria cutanea tarda
- electrical / thermal burns
- toxic epidermal necrolysis
what are the blisters with inflammation?
- bullous pemphigoid
- dermatitis herpetiformis
- linear IgA dermatosis
- bullous lupus erythematosus
- bullous drug eruption
friction blisters occur in what layer?
suprabasal
pemphigus vulgaris and vegetans occur in what layer?
suprabasal
herpes simplex and zoster blisters occur in what layer?
suprabasal
SSSS occurs in what layer?
subcorneal
impetigo occurs in what layer?
subcorneal
pemphigus foliaceous occurs in what layer?
subcorneal
direct IF consists of Abs against patient’s _______________ skin
perilesional
what is the pathogenesis of bullous pemphigoid?**
autoantibody against bullous pemphigoid antigens BP180 and BP230 (attach dermis to epidermis)
bullous pemphigoid is a disorder exclusively of the _________
elderly (60-80 and over)
what is the clinical picture for bullous pemphigoid?
- prodromal eruption (urticarial / papular lesions)
- evolves over weeks / months to a generalized bullous eruption
- moderate to severe pruritis
- tense bullae arise in normal or erythematous skin**
where is bullous pemphigoid NOT found?
mucosal surfaces
what is the term for edema between squamous cells?
spongiosus
subepidermal blister with eosinophils - diagnosis**
bullous pemphigoid
what is the IF for bullous pemphigoid?
linear deposition of IgG and C3 along BM
linear deposition of IgG and C3 along BM - diagnosis
bullous pemphigoid
what is the treatment for BP?
SYSTEMIC steroids (not topical) or other immunosuppressants
what is cicatricial pemphigoid? how is it treated?
- disease of elderly
- affects mucosal surfaces
- chronic and recurring
- scarring
- immunosuppressives
intensely pruritis dermatosis of pregnancy?
pemphigoid gestationis
does pruritis dermatosis of pregnancy spare the umbilicus, or involve it?
involves it
what are the features of dematitis herpetiformis?
- papules, vesicles, occasional bullae on erythematous or often urticarial base
- extensor involvement (elbows and knees)
- associated with celiac disease
a patient with celiac disease presents with papules / vesicles on an erythematous / urticarial base on extensor surfaces - diagnosis?**
dermatitis herpetiformis
what is the pathogenesis of dermatitis herpetiformis?
antibodies to tissue transglutaminase (TTG): deposit in skin to activate complement with subsequent chemotaxis of neutrophils
what serum marker is used to monitor dermatitis herpetiformis?
TTG
what is seen on IF in DH?
granular IgA deposition in dermal papillae** (clusters)
granular IgA deposition in dermal papillae - diagnosis?
DH
grouped vesicles in “cluster of jewels” appearance - diagnosis?
linear IgA bullous dermatosis (LABD)
granular IgA deposition along BM** - diagnosis?
LABD
PCT is due to decreased activity of what enzyme?
- uroporphyrinogen decarboxylase
what builds up in PCT?
- uroporphyrins
- coproporphyrins
sporadic PCT is associated with what disease?
Hep C
- blisters on light exposed skin particularly hands
- tense bullae on normal appearing background
diagnosis?
PCT
what is the histology of PCT?
cell poor subepidermal blister (non-inflammatory)
histology shows cell poor subepidermal blister - diagnosis?
PCT
what is the IF in PCT?
superficial blood vessels with circumferential IgG deposition
what is the pathogenesis of pemphigus vulgaris?**
formation of autoantibodies to the intercellular layers of the epidermis, leading to spontaneous blistering or fissures resulting from minor trauma
PV is more common in what demographic?
Jewish / mediterranean descent age 40-60
how does PV differ from BP?
- PV: numerous stages of blisters exists simultaneously
- PV: oral mucosa involved
- PV: can be fatal
antibodies in PV are directed against which proteins? what are their functions?
desmoglein 1 and 3 (form intercellular bridges between squamous cells)
where does PV usually start?
oral mucosa
what is the gross appearance of PV?
flaccid vesicles on normal skin that often erode and crust from easy rupturing
what is the IF appearance of PV?**
“chicken wire” of IgG or C3
IF: “chicken wire” of IgG or C3**
PV
impetigo is caused by what organisms?
- staph aureus
- strep pyogenes
the toxin responsible for SSSS and impetigo targets what protein? what is its function?
- desmoglein 1
- cell to cell adhesion within uppermost epidermal layers
what is the inheritance of hailey hailey disease?
AD
hailey hailey disease involves a defect in _______ which leads to __________
- intercellular stores of calcium
- decreased cellular adhesion
where is hailey hailey disease seen?
felxural and intertriginous areas - axilla, groin, neck
what is the treatment for hailey hailey disease?
tetracycline
multiple discrete scaling papules in seborrheic distribution - diagnosis? what is the inheritance?
- darier’s disease
- AD
darier’s disease is due to a defect in _________ which leads to __________
- intercellular stores of calcium
- decreased cellular adhesion
presentation:
- abrupt onset pruritic crops of lesions on trunk and proximal extremities
- reddish small papules with vesicles and erosions
grover’s disease
