Diagnosis: Urticaria
Small and large edematous plaques that have become confluent.
Small and large edematous plaques that have become confluent.
Submitted by Alaa Saad. Originally posted September 23, 2010.
See case discussion.
• Urticarial vasculitis • Drug eruption • Contact dermatitis • Erythema multiforme • Bullous pemphigoid (urticarial phase) • Insect bites (papular urticaria) • Dermatographism • Mastocytosis
• Individual wheals resolve within 24 hours without residual marks — if lasting >24 hours, consider urticarial vasculitis • Acute urticaria (6 weeks): usually idiopathic; autoimmune mechanism in ~40% • CSU workup: CBC, ESR/CRP, TSH; extensive testing is low-yield • Omalizumab (anti-IgE) is FDA-approved for CSU refractory to antihistamines • Angioedema: deeper involvement — ACE inhibitor-induced angioedema is bradykinin-mediated (antihistamines won't work) • Second-generation antihistamines at up to 4× standard dose before escalating therapy
Tags: urticaria, alaa saad