W13 - Vesiculo Bullous Disorders - Thomson Flashcards
What is a vesiculobullous disorder?
Chronic inflammatory disorder
- Auto antibodies target structural proteins in desmosomal plaques in skin/mucosa
How do VB disorders appear clinically?
Vesicles / bullae
intra or sub epithelial blistering
erythema
erosions/ulsers
Pain, foetor
Mucous membrane pemphigoid (features, what is it, histopathology)
- most common vbd
- Scar formation - oesophageal, laryngeal, conjuctival
- sub epithelial blistering
- Loss of connection btw basal epithlial cells and dermis
Most common VBD
Mucous membrane pemphigoid
Etiology of mucous membrane pemphigoid
•IgG and/or IgA Auto-Antibodies target Hemi-Desmosomes in Epithelial Basement Membrane Zone (EBMZ)
Clinical variants of mucous membrane pemphigoid (4)
Desquamative gingivitis
Erythematous & hyperaemic
Small bullae formation
Extends beyond marignal gingiva
Clinical features of mucous membrane pemphigoid
- 55-65 yo
- Thick-walled bullous lesions
- Lasts several days
- Irregular erosions/ulcers after bullae burst
- Oral lesions heal without scarring
ID and diff dx
Mucous membrane pemphigoid
- large ulceration after bullae burst
- How to differ from erythroleukoplakia?
- “Creamy” looking lesion NOT white
- Flat, not raised
- looks more like blister/ulcer
How to diagnose mucous membrane pemphigoid
Take incisional biopsy from around the tissue
- “perilesional sample”
- NOT from the centre → will just crumble
- Take 2 sample
- One goes into 10% saline solution
- One becomes frozen sample
- 3:38 → listen again
Mucous membrane pemphigoid
- Epithelium detaches from underlying lamina propria
Whats going on here
Glowing effetct - autoantibody attacking membrane basement cell junction
Examples of direct immunofluorescence
Patient’s biopsy sample
Frozen
Section
Microscopy
Examples of indirect immunofluorescence
Patient’s Serum
Substrate - salt split skin
Microscopy
Whats going on here
linear igG and C3 along epithelial basement membrane zone
Tx of mucous membrane pemphigoid
- Refer to opthamology and derm
- Topical corticosteroids
- Systemic corticosteroids (prednisone)
- Immunosuppressant therapy
- Maintenance of OH
Pemphigus vulgaris
“a vulgar disease”
worse than mm pemphigoid
- potentially lethal