Urticaria and Angioedema Flashcards
Define urticaria
Rapidly developing skin condition characterised by itchy wheals, usually surrounded by erythema
Define angio-oedema
Swelling of the deeper skin tissue which often affects the lips, tongue and eyelids
Describe the classification of urticaria and angioedema
Acute urticaria +/- angioedema - occurs over <6 weeks, usually self-limiting
Chronic urticaria +/- angioedema - recurrent episodes of urticaria occurring over >6 weeks, may be inducible or spontaneous
Angioedema without urticaria- swelling of the deeper skin tissue which may be inheritable or acquired
What are the potential causes of acute urticaria?
IgE mediated causes
Foods - shellfish, peanuts, milk, eggs
Insect bites or stings
Drugs - beta lactase
Animal dander
Direct mast cell degranulation
Drugs - NSAIDs, aspiring, opioids, vancomycin
Non-IgE mediated - viral infection, radioactive contrast dye
The majority of cases of chronic urticaria are idiopathic. T/F?
True
What are the potential triggers of chronic urticaria?
Heat Cold Water Pressure Vibration Sunlight ACh release
What mode of inheritance is typical of inherited angioedema?
Autosomal dominant
What are the potential acquired causes of angioedema?
ACE inhibitors Food Autoimmune disease Lymphoproliferative disease Insect bites Idiopathic
Complement 4 levels are increased in urticaria. T/F?
False - they are decreased
What test can be used in the diagnosis of inherited angioedema?
C1 esterase inhibitor levels and function (which will be decreased)
How is acute urticaria managed?
A-E evaluation, management of anaphylaxis if present
Identify and treat the underlying cause / avoid triggers
Antihistamine
Consider corticosteroids and adrenaline in severe cases
How is chronic urticaria / idiopathic angioedema managed?
identify and avoid underlying trigger
Antihistamine
Consider H2 receptor antagonists, corticosteroids and LTRA
How is inherited angioedema managed?
C1 esterase inhibitors
What are the potential complications of urticaria +/- angioedema?
Excoriation
Skin infections
Treatment related sedation
