From: Urticaria and angioedema
 | Family history | Complement levels/laboratory findings | ||
---|---|---|---|---|
C4 | C1-INH antigen | C1-INH function | ||
HAE-1 HAE-2 | Yesa | ↓ ↓ | ↓ Normal or ↑ | ↓ ↓ |
HAE-nC1-INH | Â | Â | Â | Â |
 FXII mutation | Yes | Normal | Normal | Normal |
 Unknown cause |  |  |  |  |
AAE | No | ↓ | Normal or ↓ | ↓ |