Urticaria

Question 1

What is urticaria?

Answer 1

It is a skin condition characterised by development of pruritic, erythematous raised wheels which may vary in size. Single lesion does not last for long than 24h.
Angioedema is a deeper form of urticaria with swelling in dermis and epidermis

Question 2

WHat is the definition of acute and chronic urticaria?

Answer 2

Acute < 6 weeks.
Chronic > 6 weeks.

Question 3

What are the risk factors for urticaria?

Answer 3

Allergens (food, meds, insect stings),
Physical stimuli
Infections
Autoimmune
Stress and emotional
Genetics

Question 4

What is the pathophysiology of urticaria?

Answer 4

Involves release of histamine and other mediators from mast cells and basophils leading to increased vascular permeability and formation of wheels.
Immune type and non immune types

Question 5

What are the signs and symptoms of urticaria?

Answer 5

Pruritis which is often intense,
Erythematous wheals with well defined borders
Rapid onset and resolution
Occasionally angioedema

Question 6

What is the differential diangosis for urticaria?

Answer 6

Angioedema without wheals,
Dermatits,
Drug eruptions,
Erythema multiforme
Vasculitis (consider if lesions remain for longer than 24 h)
Autoimmune disorders

Question 7

What are the investigations for urticaria?

Answer 7

Usually clinical diagnosis.
Can do allergy testing for suspected allergen
Bloods to assess inflammatory markers
Urinalysis if suspect vasculitis
Skin biopsy if need to confirm condition

Question 8

What is the management of urticaria?

Answer 8

1. identify and remove stimuli.
2. First line - non sedating antihistamine for 6 weeks
3. Second line - LTRA or omalizumab. If severe can give short coarse steroids.
4. Patient education (avoid triggers) and regular follow up

Question 9

Which patients with urticaria should be referred to derm?

Answer 9

1. People with urticaria which is painful or persistent.
2. Symptoms which are not well controlled on antihistamines,
3. Angio-oedema with no wheals and who don’t respond to treatment
4. Severe urticaria thought to be due to food/latex
5. Chronic inducible urticaria

Question 10

What are some complications of urticaria?

Answer 10

Respiratory compromise, psychological distress, side effects from long term meds

Question 11

What are some examples of drugs which can cause urticaria?

Answer 11

Aspirin, penicillin, NSAIDs, opioids.