Table 1.

Clinical phenotypes and serum concentrations of complement protein in the complement-deficient individuals.

Deficient individuals	Clinical findings	C1q (%)† (78–131)‡	C2 (%) (77–159)	C3 (g/l) (0·77–1·38)	C4 (g/l) (0·12–0·33)	C5 (%) (72–171)	P (%) (54–157)	FB (%) (59–154)	MBL (g/l) (0·1–6·0)	C4BP (%) (58–102)
C1qD-1	Recurrent infections	<0·1	84	1·15	0·19	75	128	95	4·2	152
C1qD-2	SLE	<6	n.d.§	1·59	0·39	n.d.	n.d.	n.d.	n.d.	n.d.
C4D	SLE	91	98	1·37	0	145	137	189	1·0	190
C2D-1	Pneumonia and UCTD	133	0	1·48	0·37	125	198	86	0·2	175
C2D-2	Septicaemia	97	0	1·47	0·41	135	129	80	<0·1	143
C3D	Recurrent meningitis and septicaemia	167	100	<0·06	0·16	95	123	132	2·6	97
PD	Healthy	186	185	1·62	0·29	130	0	147	<0·1	167
MBLD	Healthy	122	105	1·11	0·2	127	79	82	<0·1	112

^†% of normal serum pool;

^‡reference interval;

^§not done; SLE, systemic lupus erythematosus; UCTD, undifferentiated connective tissue disease; MBLD, mannose binding lectin-deficient; FB, factor B; C4BP, C4-binding protein; PD, properdin.