Derm - Urticaria Flashcards
What is urticaria also called?
Hives
What is urticaria?
Small itchy lumps that appear on the skin
What is urticaria associated with?
Patchy erythematous rash
Can be localised or widespread
What is the pathophysiology of hives?
Release of histamine and other pro-inflammatory chemicals by mast cells
May be part of allergic reaction or autoimmune reaction in chronic idiopathic urticaria
What are the causes of acute urticaria?
- Allergies to food, medications or animals
- Contact with chemicals, latex or stinging nettles
- Medications
- Viral infections
- Insect bites
- Dermatographism (rubbing of skin)
What is chronic urticaria?
Autoimmune condition
Autoantibodies target mast cells, t his causes the release of histamines
How is chronic urticaria sub-classified?
Depends on the cause
- Chronic idiopathic urticaria
- Chronic inducible urticaria
- Autoimmune urticaria
What is chronic idiopathic urticaria?
Recurrent episodes of chronic urticaria without a clear underlying cause of trigger
What is chronic inducible urticaria?
Episodes of chronic urticaria induces by certain triggers
What can chronic inducible urticaria be triggered by?
Sunlight
Temperature change
Exercise
Strong emotions
Hot or cold weather
Pressure
What can cause autoimmune urticaria?
SLE
How is urticaria managed?
Antihstiamines
Fexofenadine is the antihistamine of choice for chronic urticaria
Oral steroids can be considered as a short course for severe flares
In problematic urticaria what specialist treatment can be used?
Anti-leukotrienes e.g. montelukast
Omalizumab
Cyclosporin
