Clinical features differentiating bradykinin-mediated HAE and histamine-mediated angioedema (1), (2)
| Features | Hereditary angioedema (bradykinin-mediated) | Histamine-mediated angioedema |
|---|---|---|
| Age of onset | Often first to second decades | Any |
| Speed of onset | Hours | Minutes |
| Attack duration (without treatment) | 3–5 d | Several hours |
| Predominant attack location | Extremities, face, upper airways, genitourinary tract, gastrointestinal tract or bowel wall | Anywhere, although face (eyelids, lips) and extremities are common |
| Urticaria or pruritus | Rare, can have erythema marginatum | Common |
| Abdominal pain or swelling | Common | Rare |
| Triggering factors | Trauma, infections, stress, hormonal changes (e.g., estrogen, pregnancy), ACE-i; can also be random | Allergies, infections, stress, NSAIDs or ASA; often spontaneous |
| Response to antihistamines, corticosteroids and epinephrine | No | Yes |
Note: ACE-i = angiotensin-converting enzyme inhibitor, ASA = acetalycylic acid, HAE = hereditary angioedema, NSAID = nonsteroidal anti-inflammatory drug.