Overview

• Self-limited, localised swelling, where fluid extravasates into interstitial tissue

Clinical features

• Onset minutes to hours

• Spontaneous resolution in hours to days

• Asymmetric

• Usually not gravity dependent

• Face, lips, larynx and bowels

Types

• Mast cell-mediated

  • Allergic reactions to food or insect stings

  • Histamine is prominent

  • Urticaria, pruritus, bronchospasm, throat tightness, hypotension

• Bradykinin mediated

  • Usually over 24 t o36 hours

  • No urticaria, bronchospasm or allergic reactions

  • Resolves 2 to 4 days

Sites

• Larynx

• Lips, tongue, uvula

• Skin and mucous membranes

• Bowel wall

  • ACEI related

  • Acquired C1 inhibitor deficiency

  • HAE

Evaluation

• Just angioedema

  • CRP, ESR, C4

  • If C4 low then further testing for HAE or acquired C1-INH deficiency

• Angioedema + urticaria

  • Different work up for urticaria

• Angioedema + anaphylaxis

  • Serum tryptase might help

  • Often mast cell mediated

• Angioedema due to allergen

  • IgE testing

  • Variable sensitivity and specificity

Treatment

• Allergic reactions

  • H1 antihistamines

  • Gucocorticords

• ACEI induced

  • Discontinue

• C1-inhibitor

  • Replace

• Recurrent idiopathic

  • Non sedating antihistamines

  • Montelukast