Pemphigoid Flashcards
What is pemphigoid?
A vesiculobullous condition in which autoimmune antibodies target BP180 and BP230 antigens in basement membrane.
This activates complement, which causes a sub epithelial split from underlying connective tissue. Oedema fluid collects in this split and forms a blister.
High morbidity and mortality rate.
What is the presentation of pemphigoid?
Thick walled blisters (full thickness of epithelium) which last long enough for the patient to notice them.
90% presents with desquamative gingivitis.
Can also involve the eyes/ genitals therefore MDT required
What is desquamative gingivitis?
Extensive inflamed, peeling gingiva and separation/ loss of epithelium.
Extends full width of attached gingiva and beyond to alveolar mucosa
What is symblepharon?
Scarring of the conjunctiva of eye which can cause blindness.
Complication of pemphigoid
What investigations would be carried out for pemphigoid?
2 separate biopsy from peri lesional tissue for H&E staining and direct immune fluorescence
Blood tests- serum, detecting circulating autoantibodies
Why are 2 separate biopsy’s required?
The fixative used for H&E staining (formalin) destroys the protein structure and antigenic it’s of the tissues for DIF
Why is DIF results not always reliable?
There may be different antibodies involved in the disease process (not just BP180/ BP230)
What are the results for serum tests in pemphigoid (and pemphigus)?
Pemphigoid - circulating autoantibodies, IgG/ IgA which binds to basement membrane.
Pemphigus - IgG which binds to desmosomes.
In pemphigoid, what are the histology findings?
Separation of full thickness of epithelium at the level of the basement membrane without epithelial damage
In [pemphigoid, what are the direct immunofluorescence results?
Linear binding of C3/ IgA/ IgG at the basement membrane
Why is a perilesional biopsy taken?
Often no epithelium is present on the blister (biopsy would therefore come back as non-specific inflammation)
Intact mucosa will show the same features
What is the aim of treatment in pemphigoid?
To halt the progression of disease, alleviate symptoms and prevent complications
What are some of the treatment options for pemphigoid?
Benzydamine mouthwash (analgesic) - eg difflam
Antiseptic mouthwash (chlorohexidine 0.2% 10ml)
Topical steroids - betamethasone 500mg tablets as mouthwash (4x daily, 3 min rinse- do not swallow)
Tacrolimus cream in gingival veneer
Often combined with systemic steroids - prednisolone
Immune modulating drugs eg azathioprine
Why are regular blood tests required when a pt is taking systemic steroids?
To screen for drug toxicity
What is an example and the function of immune modulating drugs
Eg azathioprine
Dampens down the immune system so the dose of steroid can be reduced.
