W13 - Vesiculo Bullous Disorders - Thomson Flashcards
(41 cards)
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
Features of pemphigus vulgaris
- Potentially lethal
- Skin and oral mucosa affected
- chronic
- Intra-epithlial blistering
- Can be drug induced
Cellular etiology of pemphigus vulgaris
IgG autoantibody binding targets desmosomal proteins interfering with cell adhesion
Clinical appearance of pemphigus vulgaris (3)
- Painful, fragile, fluid-filled blisters
- Burst in a few hours
- shallow ulcers/ erosions
What tissues are affected by pemphigus vulgaris
Affects both palates, buccal mucosa, lips and gingiva
Pemphigus vulgaris
ID and whats going on
IgG, IgM and C3 bound to intercellular areas of epithelium
- – Fluorescently-labelled Antibodies to identify bound Auto-Antibodies
What is the treatment of pemphigus vulgaris
- Refer to dermatologist
- Systemic corticosteroids (prednisone)
- immunosuppressive therapy
- Topical corticosteroids
- Maintenance of OH
Diff dx of mm pemphigoid and pempigus vulgaris (4)
- Paraneoplastic Pemphigus (Haematological Malignancies)•
- Erythema Multiforme•
- Epidermolysis Bullosa•
- Angina Bullosa Haemorrhagica
