Vesiculobullous Disease Flashcards
What immune reactions can the body produce?
Hypersensitivity reactions type 1-5
Immunogenic responses
- cell mediated immunity
- antibody mediated immunity
Give some diseases that produce local responses in the oral mucosa
Aphthous ulcers
Lichen planus
Orofacial ganulomatosis
(All cell mediated immune responses)
Give some systemic diseases that can present with localised oral mucosa lesions
Erythema multiforme (type 3 hypersensitivity)
Pemphigus (antibody mediated)
Pemphigoid (antibody mediated)
Lupus erythematosis
Systemic sclerosis
Sjogrens
Why are common blistering skin lesions often connected to oral blistering?
Both oral mucosa and skin share common antigens due to having the same embryonic origin
Difference between vesicle and blister?
Size
Vesicle 1-2mm
Blister is larger
How does immunological skin disease result in a blister or vesicle?
Auto-antibody attack on skin components causes a loss in cell - cell adhesion
This forms a split in the thin that:
- fills with inflammatory exudate
- forms vesicle / blister
Split caused by attack on protein desmoglein which in turn causes splitting of desmosomes that hold cells together
What does direct and indirect immunofluorescence show
Direct = antibodies bound to tissue
Indirect = antibodies not yet bound to tissue and is in plasma
What is angina bullous haemorrhagica?
Describe it
‘Blood blisters in the mouth’
- Benign
- rapid onset
- appear in a few minutes and then burst after around an hour
- relatively painless
- significant lesions can appear around vibrating line that can give pt feeling of occlusion of airway
Most common oral blistering condition
How treat angina bullish haemorrhagica?
Symptomatic relief
Chlorhexadine mouthwash or difflam spray
Reassure it is benign
What is pemphigoid? What causes it?
Thick walled blisters of the full epidermis
- clear or blood filled
- on skin or mucosa
Caused by sub epithelial antibody attack.
- antibodies cause separation of the epithelium at the basement membrane from the connective tissue by attacking hemidesmosomes
- achieves this as IgG and IgA antibodies bind to BP180 protein to form an immune complex. These immune complexes activate the complement system.
- triggers an influx of inflammatory cells and formation of a blister in the area.
What is the best test for pemphigoid?
Direct immunofluorescence
- pemphigoid antibodies bound to the antigen of the basement membrane
- causing fluorescence
- C3 and IgG detected
How manage pemphigoid?
Steroids
Immune modulating drugs - azathioprine
What is pemphigus?
Circulating antibodies IgG attack desmoglein 1 and desmoglein 3 leading to destruction of the desmosomal complex that holds keratinocytes together.
Intra epithelial blisters form
- blisters burst and spread
- variable number of cells above so easily bursts
- results in epithelial / mucosal erosions
Oral lesions precursor to skin lesions by up to 3 years
How tell difference between pemphigoid and pemphigus?
Rare to see intact bulla in pemphigus
Intact bulla on ora mucosa = pemphigoid
Test for pemphigus?
Immunofluorescence
- basket weave pattern
Vs linear pattern in pemphigoi
C3 and IgG found again
Tx for pemphigus?
Prognosis?
High dose steroids
Fatal without treatment
Now, often complications of treatment are the major cause of death
Intra oral manifestations of pemphigoid?
Bullae formation - these quickly rupture to leave erosions of the mucosa
Erythema - open sores or shallow wounds
Stricture - scarring - restricted movement or narrowing of oral cavity / airway
Extra oral manifestations of MMP?
Ocular involvement - inflammation of the eyes - visual impairment
Skin lesions - blistering and erosions of the skin - skin discomfort
Bullae and erosion of other mucous membranes
All can lead to psychosocial effects
What is nikolskys sign?
Lateral pressure placed on a bullae
Positive sign = the exfoliation of the outermost layer by slight rubbing of the skin
How can indirect immunofluorescence / Elisa testing be used to test for MMP?
IIF - detects circulating IgG autoantibodies
Elisa testing - tests for BP180 and BP230
Histological signs of pemphigus vulgaris?
Perilesional biopsy
Acantholysis - loss of cell-cell adhesion in the epithelium
Tzanck cells - individual large round keratinocytes with hypertrophic nucleus
Inflammatory exudate within epithelial layers
What is ELISA testing?
Enzyme linked immunosorbent assay
Epidemiology of MMP and PV?
50/60 years old
Slightly more common in females
PV more common in Jewish-American population
Basically - What is EM?
Spectrum disorder with skin and mucosal ulceration with varying oral involvement
