Erythema Multiforme Flashcards
Define Erythema Multiforme?
An acute hypersensitivity reaction of the skin and mucous membranes
What is Stevens-Johnson Syndrome?
A severe form of Erythema Multiforme with bullous lesions and necrotic ulcers
What is the aetiology of Erythema Multiforme?
Degeneration of basal epidermal cells
Development of vesicles between cells in the basement membrane
Lymphocytic infiltrate around the blood vessels and at the dermo-epidermal junction
A precipitating factor is only identified 50% of the time
What are the precipitating factors for Erythema Multiforme?
Drugs Infection Inflammatory Malignancy Radiotherapy
What are some examples of drugs that can cause Erythema Multiforme?
Sulphonamides
Penicillin
Phenytoin
What are some examples of some infections that can precipitate Erythema Multiforme?
HSV EBV Adenovirus Chlamydia Histoplasmosis
What are some examples of inflammatory causes of Erythema Multiforme?
Rheumatoid arthritids
SLE
Sarcoidosis
Ulcerative Colitis
What are some examples of malignancies that can cause Erythema Multiforme?
Lymphomas
Leukaemia
Myeloma
What is the epidemiology of Erythema Multiforme?
Any age group
Mainly in CHILDREN and YOUNG ADULTS
TWICE as common in MALES
What are the presenting symptoms of Erythema Multiforme?
Non-specific prodromal symptoms of upper respiratory tract infection
Sudden apperance of itching/burning/painful skin lesions
Skin lesions may fade leaving pigmentation
What are the signs of Erythema Multiforme on physical examination?
Classic target (bull’s eye) lesions with a rim of erythema surrounding a paler area
Vesicles/bullae
Urticarial plaques
Lesions are often symmetrical and distributed over the arms and legs including the palms, soles and externsor surfaces
What is Stevens-Johnson syndrome characterised by?
Affecting > 2 mucous membranes (e.g. conjunctiva, cornea, lips, mouth, genitalia)
Systemic symptoms (e.g.sore throat, cough, fever, headache, myalgia, arthralgia, diarrhoea/vomiting)
Shock (hypotension and tachycardia)
What investigations can we do for Erythema Multiforme?
Usually unnecessary - Erythema Multiforme is very much a clinical diagnosis
Bloods
Imaging
Skin Biopsy
What bloods would you do for Erythema Multiforme?
High WC
Eosinophils
ESR/CRP
Why do we do imaging for Erythema Multiforme?
Exclude sarcoidosis and atypical pneumonia
