Skin Blisters Flashcards
Name some blistering skin conditions
Bollous pemphigoid,
Pemphigus vulargis.
Autoimmune causes
What is the pathophysiology of bollous pemphigoid?
Autoantibodies target hemidesmosomes that bind the basal keratinocytes to basement membrane. This causes sub-epidermal blisters
What are the clinical features of bollous pemphigoid?
Usually affects older people (60-80) and presents with itchy rash that develops into tense blisters typically around flexures.
Nikolskynegative
Blisters health without scars
Typically no mucosal involvement
What are the investigations for bollous pemphigoid?
Biopsy for immunofluorescence (IgG and C3 at dermoepidermal junction).
Anti BP180 and Anti-BP230 antibodies
What is the treatment for bollous pemphigoid?
Topical steroids at onset of symptom (itch),
Doxycycline for anti-inflammatory,
Oral steroids until no further lesions for one year.
If relapse during steroid withdrawal then start azathioprine/mycophenolate.
Oral steroids are the mainstay of treatment
What is the pathophysiology of pemphigus vulgaris?
IgG antibodies targeted against desmosomes within the epidermis (what holds keratinocytes together.
This leads to development of blisters within the epidermis which are flaccid and deroofed.
It is more serious
Age 40-60.
What are the clinical features pemphigus vulgaris?
Flaccid, thin walled blisters leading to erosions across the body.
Mucus membrane involvement in 90%
Nikolsky’s sign positive
Patients are very unwell and there is high mortality
What are the investigations for pemphigus vulgaris?
Biopsy for immunofluorescence
Detection of antibodies against desmoglein 1 and 3 using indirect immunofluroesence or ELISA
What is the treatment for pemphigus vulargis?
High dose oral steroids to induce remission. May need rituximab
Topical steroids for mucous membranes
Immunosupressants to reduce corticosteroid dependence.
Steroids are first line
What are the risk factors for pemphigus vulgaris?
Genetics - Jewish and Asian
Drugs - Penicillamine, captopril
