Table 3.

Comparison of HAE and AAE [23, 33]

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

Adapted from Betschel et al. [23], Cicardi et al. [33]

^aIn approximately 25% of patients, no family history is identified; the disorder results from spontaneous mutation of the C1 inhibitor gene