Angioedema

(J Allergy Clin Immunol 2013;131:1491)

• Localized swelling of skin/mucosa; involves face, lips, tongue, uvula, larynx, and bowels

• Etiologies: mast cell-mediated (eg, NSAIDs); bradykinin-mediated (eg, ACEI, ARNi, hereditary angioedema, acquired C1 inhibitor deficiency); idiopathic

• Diagnosis: C4 and C1 inhibitor level, tryptase (if suspect anaphylaxis), ESR/CRP

• Rx: intubation if risk of airway compromise. Allergic angioedema: H1/H2 antihist., steroids.

If 2° ACEI: d/c ACEI, antihist., icatibant (bradykinin-receptor antag; NEJM 2015;372:418).

Hereditary angioedema: plasma-derived C1 inhibitor, ecallantide (kallikrein inhibitor)