Pemphigus Flashcards
what is pemphigus
group of autoimmune blistering diseases, of which pemphigus vulgaris is the most common type
discuss the epidemiology of pemphigus vulgaris
most commonly presents in middle age population
more common in ashkenazi jew population
discuss the pathogenesis of pemphigus vulgaris
development of autoantibodies to desmosomal proteins sees loss of epithelial cell - cell adhesion
Antibodies work against desmoglein protein in desmosomes causing epithelial cells to lose adhesion and intra epithelial bullae form
what desmoglein proteins are expressed in the skin and mucous membranes and what does this mean
DsG 1 - expressed throughout entire skin epidermis, DsG 3 just in lower epidermis
DsG 1 and DsG 3 expressed in mucosal epithelium but DsG 3 in greater amounts
anti DsG 1 - skin lesions
anti DsG 3 - mucosal lesions
anti DsG 1 and 3 - skin and mucosal lesions
discuss extra oral manifestation of pemphigus vulgaris
appears as erosion rather than bullae
can affect other mucous membranes e.g nose, throat, eyes, genitals
Flaccid skin blisters which develop into oozing erosions (infection risk)
discuss intra oral manifestations of pemphigus vulgaris
erosions rather than blisters, irregular appearance to erosions
soft palate, buccal mucosa and lips most commonly affected
desquamative gingivitis may be present
discuss the histology of pemphigus vulgaris
intra epithelial gaps produced by acantholysis. Typically this loss of attachment occurs in stratum spinosum (prickle cell layer) so basal cells are base of lesion and still attached to lamina propria
Acantholytic prickle cells may be seen singly or in clusters within vesicle fluid and are referred to as tzanck cells
acantholysis
loss of intracellular connections, e.g desmosomes, between epithelial cells
tzanck cells
acantholytic epithelial cells seen within blister fluid in pemphigus vulgaris
what will be seen on a direct immunofluroescence test of pemphigus vulgaris
will show IgG antibodies affecting the entire epidermis - basket weave pattern
why may an ELISA test be useful in pemphigus vulgaris
can be used to quantify DsG antibody titres. Anti DsG 3 antibody tite is related to disease severity
what substrate is used to aid indirect immunofluorescence when investigating pemphigus vulgaris
monkey oesophagus
why was pemphigus vulgaris associated with high mortality rates in the past
before the production of synthetic corticosteroids
skin lesions would become infected and lead to septicemia
what is the most common treatment of pemphigus vulgaris
usually begins with high levels of prednisolone to get disease under control
Immunosuppresive agents such as azathioprine or mycophenolate mofetil may also be used as steroid sparing agents so prednisolone dose can be reduced without losing control of disease
for pemphigus vulgaris that is difficult to control by prednisolone, what further treatment may be used
IV immunoglobin therapy
monoclonal antibody therapy e.g rituximab
