Immunobullous disorders Flashcards
in IB diseases, are blisters a primary or secondary feature
they are a primary feature
name the 3 IB disorders
- bullus pemphigus
- bullus phempigoid
- dermatitis herpetitformis
describe nikolsky’s sign and what it indicates if positive
in a +ive sign, the top layers of the skin slip away from lower layers when slightly rubbed
indicates plane of cleavage within epidermis
is nikolsky’s sign +ive or negative in bullous pempigoiD
pemphigoiD is a Deep blister - its sub epidermis is nikolsky’s sign -ive
is nikolsky’s sign +ive or negative in bullous pemphiguS
pemphiguS is a Superficial blister - it is epidermal, so isnikolsky’s sign +ive
pemphigus is a viral disease. true?
no - pemphigus is a rare autoimmune disease
what is the most common subtype of pemphigus
pemphigus vulgaris (80%)
what antibodies attack what in pemphigus vulgaris
IgG antibodies attack demoglein 1 & 3
what is the role of desmoglein 3
to maintain desmosomal attachments -
if its attacked by IgG antibodies, desmosomal attachments are lost and pemphigus vulgaris occurs
what is the end result of pemphigus
acantholysis -
loss of cohesion of the keratinocytes / lysis of intracellular adhesion types
pemphigoiD has a higher mortality than pemphiguS if left untreated. true?
no - pemphiguS has a higher mortality than pempigoiD if left untreated
what do the IgG antibodies react with in pemphigoiD and what does this cause
the antigen on the hemidesmasomes
this antigen anchors the basal cells to the basement membrane
this results in local complement activation and tissue damage
what GI disease does dermatitis herpetiformis have strong associations with
coeliac disease
90% of those with DH have gluten sensitivity
what gene is dermatitis herpetiformis associated with
HLA DQ2
what is the hallmark feature of dermatitis herpetiformis
papillary dermal micro abscesses
