Urticaria Flashcards
(11 cards)
What is urticaria?
Urticaria (AKA hives) consists of erythematous, blanching, oedematous, non-painful, pruritic lesions that develop rapidly, usually over minutes
- Typically lasts less than 24 hours and leaves no residual skin markings upon resolution
What are the different types of urticaria a patient may present with?
- Acute Urticaria → mainly allergy related (IgE-mediated)
- Chronic Urticaria → may be triggered by heat, cold, pressure, sunlight, vibration, acetylcholine release, and water
What is “angiooedma”?
“swelling that is similar to hives, but the swelling is under the skin instead of on the surface.”
* Angiooedema occurs when the deep tissues, the lower dermis and subcutaneous tissues are involved and become swollen.
* Angio-oedema occurs in association with urticarial in about 40% of cases
What causes urticaria?
- Caused by activation of mast cells in the skin, resulting in the release of histamines
- The cytokine release leads to capillary leakage, which causes swelling of the skin and vasodilation –> erythematous appearance
- Aspirin is a common cause of urticaria
What are some possible triggers of urticaria?
- ACUTE urticaria
* Allergies (foods, bites, stings)
* Viral infections
* Skin contact with chemicals
* Physical stimuli - CHRONIC urticaria
* Chronic spontaneous urticaria - medication, stress, infections
* Autoimmune
Summarise the epidemiology of urticaria
- 15% of general population experience urticaria at some point in life
- Acute is much more common than chronic urticaria
What are the presenting symptoms/ signs of urticaria?
- Erythematous Oedematous Lesions → pale, pink, smooth raised skin (wheals)
- Pruritus
- Resolution within 24 hours
- Swelling of face, tongue, or lips → up to 40% of urticaria cases have associated angio-oedema
- Lesions blanch when palpated
What investigations are used to diagnose/ monitor urticaria?
ESR & CRP→ if urticarial vasculitis suspected
How is urticaria managed?
- Trigger identification & avoidance
- 1st Line → Antihistamines (loratadine)- non- sedating
- In acute urticaria a sedating antihistamine (e.g. chlorphenamine) may be considered for night-time use for troublesome sleep symptoms - Systemic Corticosteroid (Prednisolone) → for severe or recurrent episodes
What complications may arise following urticaria?
excoriations, sedation (side effect of antihistamines), skin infections
Describe the prognosis of urticaria
excellent, vast majority of patients respond well to therapy with non-sedating antihistamines, and the condition is short-lived
