Classification and Diagnosis of Urticaria

Urticaria is a multicausal and heterogeneous disease characterized by an onset of wheals and/or angioedema. More than one subtype of urticaria can coexist in any given patient. Subtypes of urticaria display diverse but common histological features as seen in a wide variety of inflammatory reactions, and therefore have no diagnostic value. The current guidelines recommend a simple classification based on clinical symptoms, their duration, and if they are inducible. Disease activity and level of symptoms must also be considered when assessing the severity of urticaria, and for this the UAS7 patient self-assessment is used. Acute, chronic, and spontaneous chronic urticaria also differ in the diagnostic work up.