Bullous diseases

Bullous diseases

1. Pemphigus

   • Pathogenesis
     • IgG & C3 deposits between keratinocytes causing acantholysis
       • Acantholysis = loss of cohesion between keratinocytes
     • Target antigen
       • DSG 1, DSG 3 (desmoglein) for pemphigus Vulgaris
   • Types
     • Paraneoplastic pemphigus
       • Associated with
         • Non hodgkins lymphoma
         • Lymphocytic leukemia
       • Lichenoid like lesions
     • Pemphigus folaceus
       • No mucosal involvement
     • Pemphigus vulgaris
       • Treatment
         • Mild
           • Systemic steroids
         • Moderate
           • Systemic + azothiprine
   • Who gets it?
     • Men = women
     • 30-60yrs
     • Jewish
     • Mediterranean
   • Death rate
     • If treated with steroids
       • 10% die
     • If untreated
       • 75% die
   • Aetiology
     • Drugs
     • Garlic
     • Surgery
     • Stress
   • Clinical features
     • Nikosky's sign positive
     • Intra-oral
       • Red erosions/ulcers
         • Affects
           • Buccal mucosa
           • Palate
           • Lips
     • Extra-oral
       • Ulceration
         • Conjunctiva
         • Nasal mucosa
         • Skin
           • Pemphigus vulgaris
             • Intact skin blisters
               • When they burst become crusted
         • Pharynx & larynx
   • Diagnosis
     • Biopsy anywhere for direct immunofluorescence
       • Because high level of circulating antibody
       • Shows intercellular IgG in a net like pattern
   • Histology
     • Intra-epithelial blister
     • IgG & C3 intercellular

2. Pemphigoid

   • MMP
     • Diagnosis
       • Direct immunofluorescence
         • IgG, IgA & C3 at basement membrane
         • Biopsy adjacent to lesion
     • Clinical features
       • 1) Mouth
         • 90% have oral involvement
         • Sites
           • Gingiva
           • Buccal mucosa
           • Tongue
           • NOT lips
           • Palate
         • What do you get?
           • Patches, blisters & erosions
           • Desquamative gingivitis
       • 2) eye
       • Nikolsky sign positive
       • 3) Vulvovaginal region
       • 4) RARELY skin
     • Who gets it?
       • Elderly women
     • Histology
       • Subepithelial blister
     • Treatment
       • Oral only
         • 1. Topical steroids
           • 1. Clobetasol propionate in orobase
           • 2. Triamcinolone acetonide
             • Need to give an antimycotic too
         • 2. Systemic steroids
         • 3. Azothiprine
       • Ocular
         • 1. Dapsone
         • 2, Cyclophospamide
           • BUT infertility
     • More common
   • Angina bullosa haemorrhagica

3. Generic blistering disease points

   • Check these things in a patient with blistering
     • Nikolskys sign
     • Ocular lesion
     • Skin lesion
   • Tests available
     • Histology
     • 1. Biopsy Direct immunofluorescence
     • 2. Indirect immunofluorescence
       • Salt split skin
         • Better than normal indirect immunofluorescence because more sensitive to autoantibodies
     • 3. ELISA

4. Dermatitis Herpetiformis

   • Diagnosis
     • Direct immunofluorescence
       • IgA deposits
   • Who gets it?
     • Men=women
   • Sub-epithelial blister