Urticaria Flashcards
What is urticaria due to?
The release of histamine and other pro-inflammatory chemicals by mast cells in the skin.
How does urticaria present?
- pale, pink raised skin.
- Variously described as ‘hives’, ‘wheals’, ‘nettle rash’
- pruritic
How is urticaria commonly described?
‘hives’, ‘wheals’, ‘nettle rash’
What is acute urticaria triggered by?
Something that stimulates the mast cells to release histamine.
What might stimulate the mast cells to release histamine?
- Allergies to food, medications or animals
- Contact with chemicals, latex or stinging nettles
- Medications
- Viral infections
- Insect bites
- Dermatographism (rubbing of the skin)
What type of condition is chronic urticaria?
Autoimmune disease
What is chronic urticaria due to?
Autoantibodies target mast cells and trigger them to release histamines and other chemicals.
How can chronic urticaria be sub-classified?
- Chronic idiopathic urticaria
- Chronic inducible urticaria
- Autoimmune urticaria
What is chronic idiopathic urticaria?
Recurrent episodes of chronic urticaria without a clear underlying cause or trigger.
What is chronic induced urticaria?
Episodes of chronic urticaria that can be induced by certain triggers,
What are possible triggers of chronic induced urticaria?
- Sunlight
- Temperature change
- Exercise
- Strong emotions
- Hot or cold weather
- Pressure (dermatographism)
What is autoimmune urticaria?
Chronic urticaria associated with an underlying autoimmune condition, such as systemic lupus erythematosus.
What is the main management of urticaria?
Antihistamines
What is usually the antihistamine of choice for urticaria?
Fexofenadine
What might be given for a short course for severe flares?
Oral steroids- prednisolone
