Complement Diagnostics: Concepts, Indications, and Practical Guidelines

Table 2

Complement pathology, differential diagnostics.

Analyses	HAE/AAE	SLE, urticarial vasculitis	PSGN	MPGN; II and III	Complement; deficiencies
CP	N	L	L	L	*
AP	N	N (L)	L	L	*
C1INH (conc)	L	N	N	N	*
C1INH (funct)	L	N	N	N	*
C1q	(L)	L	N	N	*
C4	L	L	N	N	*
C3	N	L	L	L	*
C5	N	—	L	(L)	*
Factor B	N	N	L	N	*
Properdin	N	—	L	N	*
C3d	N	H	H	H	N
C3d,g/C3	N	H	H	H	N

*Variable (dependent on which component is defective); N: normal; L: low; H: high.