Urticaria

Question 1

What is urticaria?

Answer 1

Urticaria are also known as hives. They are small itchy lumps that appear on the skin.

Question 2

How does urticaria present?

Answer 2

They are small itchy lumps that appear on the skin. They may be associated with a patchy erythematous rash. This can be localised to a specific area or widespread. They may be associated with angioedema and flushing of the skin. Urticaria can be classified as acute urticaria or chronic urticaria.

Question 3

Briefly describe the pathophysiology of urticaria

Answer 3

Urticaria are caused the release of histamine and other pro-inflammatory chemicals by mast cells in the skin. This may be part of an allergic reaction in acute urticaria or an autoimmune reaction in chronic idiopathic urticaria.

Question 4

What causes acute urticaria?

Answer 4

Acute urticaria is typically triggered by something that stimulates the mast cells to release histamine. This may be:

• Allergies to food, medications or animals
• Contact with chemicals, latex or stinging nettles
• Medications
• Viral infections
• Insect bites
• Dermatographism (rubbing of the skin)

Question 5

What is chronic urticaria?

Answer 5

Chronic urticaria is an autoimmune condition, where autoantibodies target mast cells and trigger them to release histamines and other chemicals. It can be sub-classified depending on the cause:

• Chronic idiopathic urticaria
• Chronic inducible urticaria
• Autoimmune urticaria

Question 6

What is chronic idiopathic urticaria?

Answer 6

Chronic idiopathic urticaria describes recurrent episodes of chronic urticaria without a clear underlying cause or trigger.

Question 7

What can trigger chronic inducibe urticaria?

Answer 7

Chronic inducible urticaria describes episodes of chronic urticaria that can be induced by certain triggers, such as:

• Sunlight
• Temperature change
• Exercise
• Strong emotions
• Hot or cold weather
• Pressure (dermatographism)

Question 8

What is autoimmune urticaria?

Answer 8

Autoimmune urticaria describes chronic urticaria associated with an underlying autoimmune condition, such as systemic lupus erythematosus.

Question 9

Briefly describe the management of urticaria

Answer 9

Antihistamines are the main treatment for urticaria. Fexofenadine is usually the antihistamine of choice for chronic urticaria. Oral steroids may be considered as a short course for severe flares.

Question 10

What specialist treatments can be given for urticaria?

Answer 10

In very problematic cases referral to a specialist may be required to consider treatment with:

• Anti-leukotrienes such as montelukast
• Omalizumab (which targets IgE)
• Cyclosporin