Blistering Skin Disease Flashcards
Give examples of common causes of skin blisters
Infection - HSV, VSV, impetigo, tines pedis, cellulitis
Insect bites
Trauma - burns and friction
Eczema
Give examples of immunobullous diseases
Dermatitis herpetiformis
Phemigus
Bullous phemigoid
What is the name for mechanobullous disease?
Epidermyloysis bullosa
What is epidermyloysis bullosa?
A spectrum of mechanobullous disease encompassing >30 inherited conditions in which there is mechanical fragility of the skin resulting in blistering
What are the typical features of mechanobullous disease?
Mechanical fragility of skin Recurrent blisters / erosions Poor wound healing Dystrophic /absent nails Milia (tiny white bumps) Atrophic scarring Herpetiform blistering Reticulate hyperpigmentation Exuberant granulation tissue
What investigations should be used for mechanobullous disease?
Immunofluorescence antigen mapping
Transmission electron microscopy
DNA mutation analysis
How is mechanobullous disease managed?
Wound care
Treatment of superimposed infection
Nutritional supplementation
Lifestyle advice (avoiding skin trauma)
At what age does mechanobullous disease typically present?
Birth or early infancy
What are the potential complications of mechanobullous disease?
Failure to thrive Growth retardation Anaemia Depression Deformities of the hands and feet Squamous cell carcinoma
What is pemphigus?
A group of autoimmune diseases characterised by blistering of the epidermis and/or mucosa
List the three subtypes of pemphigus in order of commonality (most common to least common)
Most common - pemphigus vulgaris
Middle - pemphigus follaceus
Least common - paraneoplastic pemphigus
Which malignancies is paraneoplastic pemphigus associated with?
Non-Hodgkin’s lymphoma
CLL
Thymoma
Describe the pathophysiology of pemphigus vulgaris and pemphigus follaceus?
IgG autoantibodies are directed against the desmosome resulting in blistering disease
Describe the pathophysiology of paraneoplastic pemphigus?
IgG antibodies and cell mediated destruction of hemidesmosomes
What investigations are used in pemphigus?
Histopathology - haemotoxylin/eosin staining
Direct and indirect immunofluoresence
ELISA looking for IgG autoantibodies
Endoscopy, CXR and CT chest in some cases to evaluate the extent of the disease
Describe the presentation of pemphigus vulgaris and pemphigus follaceus?
Chronic pruritic and/or painful erosions or superficial blisters which typically affect the oral mucosa and skin in pemphigus vulgaris and which only affect the skin (typically face, scalp and upper trunk) in pemphigus follaceus
Describe the management of pemphigus?
Wound care
Supportive care (analgesia, antiseptic baths, dental care, nutritional support)
Topical or oral corticosteroids
Biologics (Rituximab)
Oncology referral for paraneoplastic pemphigus
What is bullous pemphigoid?
A chronic acquired autoimmune disease which results in sub-epidermal blistering
What are the typical symptoms of the pre-bulbous prodromal stage of bullous pemphigoid?
Pruritus
Eczematous / urticarial lesions
Lasts weeks to months
Describe the typical appearance of bullous pemphigoid?
Tense vesicles and bullae typically appearing on the flexor surfaces of the limbs, axillae, groin and abdomen
When blisters burst, there may be crusty eroded lesions which heal with hyperpigmentation
What investigations are used for bullous pemphigoid?
Histopathology
Light microscopy
Direct and indirect immunofluorescence
ELISA
How is bullous pemphigoid managed?
Topical (or oral) corticosteroids Tacrlimus Antihistamines Steroid sparing agents - Ciclosporin or dapsone in some cases Topical antibiotics as required
What is dermatitis herpetiformis?
A rare blistering disease associated with coeliac disease
Describe the appearance of dermatitis herpetiformis?
Small, pruritic blisters and papules on the elbows, extensor surfaces of the forearms, scalp and buttock
Lesions may become crusted and eroded when scratched
What is the definitive management of dermatitis herptiformis?
Avoid gluten
How can the rash of dermatitis herpetiformis be managed?
Dapsone
Sulphonamides
