2

Urticaria vasculitis (UV) presents episodes of urticaria often associated with arthralgia and abdominal pain and rarely with glomerulonephritis. The individual lesions tend to persist longer than common wheals (1-3 days). They may reveal faint purpura and resolve with residual discoloration. The degree of clinical purpura in UV is variable. Purpuric areas may be minimal and unapparent by means of the standard visual inspection, requiring biopsy for diagnosis. Dermoscopy serves herein

Figure 7.21 Clinical appearance of transient lesions (wheals) of common urticaria (CU) in a patient with vitiligo.