. 2017 Oct 13;29(1):283–294. doi: 10.1681/ASN.2017030258

Table 3.

Clinical features, complement assessment, genetic screening, and histologic features in patients classified according to the clusters obtained through cluster analysis

Variable	Cluster 1	Cluster 2	Cluster 3	Cluster 4	Overall P Value
N	62	32	33	46
Sex, % men	61	41	55	61	0.24
Data at onset
Age, yr	15 (±11.6)	17.2 (±13)	14.5 (±10.4)	28.8 (±19.8)^a^,^b^,^c	<0.001
Microhematuria, %	90	93	94	64^a^,^b^,^c	<0.001
Gross hematuria, %	37	34	50	20^a^,^c	0.04
Proteinuria, %	93	94	85	89	0.51
Nephrotic syndrome, %	29	72^a^,^c^,^d	24	24	<0.001
Renal impairment, %	10	19	6	39^a^,^c	<0.001
Trigger event, %	38	31	23	22	0.29
Familiarity for nephropathy, %	23^c	16	3	11	0.05
Serum C3, mg/dl	34.7 (±30.2)	34.5 (±37.9)	31 (±25.6)	86.7 (±35.6)^a^,^b^,^c	<0.001
Serum C4, mg/dl	21.1 (±10.3)	19.1 (±13)	23.5 (±7.9)	23.6 (±7.5)	0.17
Plasma SC5b-9, ng/ml	1494 (±1325)^c^,^d	1558 (±1285)^c^,^d	591 (±1062)	416 (±395)	<0.001
Low serum C3 and normal C4, %	81	72^c	94	50^a^,^b^,^c	<0.001
LPV carriers, %	32	22	15	4^a^,^b	0.004
C3NeF positive, %	53	53	75	9^a^,^b^,^c	<0.001
LPV carriers and/or C3NeF, %	75	63	79	14^a^,^b^,^c	<0.001
Data during follow-up, %
Nephrotic syndrome	52	88^a^,^c^,^d	52	50	0.003
High BP	26	44	27	63^a^,^c	<0.001
CKD	18^b^,^c^,^d	47	36	54	<0.001
ESRD	2^d	6	6	22	0.003
Thrombotic microangiopathy	2	0	0	13^a^,^c	<0.01
Histologic features
Time onset to biopsy, yr, median (IQR)	0.6 (0.2–3.6)	0.2 (0.1–1.7)	0.6 (0.2–1.8)	0.4 (0.0–3.3)	0.31
Light microscopy
Sclerotic glomeruli, %	4 (±8)	8 (±15)^c	1 (±3)	17 (±21)^a^,^b^,^c	<0.001
Crescents, %	1 (±4)	3 (±9)	18 (±31)^a^,^b^,^d	4 (±10)^a	<0.001
Degree of mesangial proliferation^e	2 (±0.9)	1.4 (±1.1)^a^,^c	2 (±0.8)	1.7 (±0.9)	0.01
Degree of endocapillary proliferation^e	1.2 (±1.1)	1.6 (±1)	1.3 (±1.2)	0.5 (±0.8)^a^,^b^,^c	<0.001
Degree of interstitial inflammation^e	0.5 (±0.6)^b^,^d	0.8 (±0.6)	0.6 (±0.8)	1 (±1)^c	<0.001
Degree of interstitial fibrosis^e	0.3 (±0.6)	0.5 (±0.6)	0.3 (±0.6)	0.8 (±0.9)^a^,^c	<0.001
Degree of arteriolar sclerosis^e	0.2 (±0.5)	0.2 (±0.5)	0 (±0.2)	0.6 (±1)^a^,^b^,^c	<0.001
IF^e
C3	2.7 (±0.5)	2.7 (±0.5)	2.8 (±0.3)	2.5 (±0.7)^a^,^c	0.03
IgA	0.1 (±0.4)	0.7 (±0.8)^a^,^c^,^d	0.1 (±0.3)	0.2 (±0.7)	<0.001
IgG	0.4 (±0.7)^d	2 (±0.9)^a^,^c^,^d	0.5 (±0.8)	1 (±1.2)	<0.001
IgM	0.7 (±0.8)	1.2 (±0.9)	0.8 (±0.7)	0.8 (±1)	0.12
C1q	0.3 (±0.5)^d	1.6 (±0.9)^a^,^c^,^d	0.3 (±0.6)	0.6 (±1)	<0.001
Fibrinogen	0.4 (±0.8)	0.6 (±0.9)	0.3 (±0.8)	0 (±0.1)^a^,^b^,^c	0.01
Electron microscopy, %
Mesangial deposits	83^b^,^c^,^d	52	44	53	<0.001
Subepithelial deposits	57^c^,^d	38	19	36	0.004
Subepithelial hump-like deposits	20	14	19	16	0.88
Subendothelial deposits	84	93	9^a^,^b^,^d	66^a^,^b	<0.001
Intramembranous granular deposits	59	41	16^a^,^b^,^d	41	<0.001
Intramembranous highly electron-dense ribbon-like deposits	7	0	73^a^,^b^,^d	0	<0.001

Quantitative variables are expressed as mean (±SD) unless otherwise specified. Serum C3: reference 90–180 mg/dl; serum C4: reference 10–40 mg/dl; plasma SC5b-9: reference ≤400 ng/ml. IQR, interquartile range.

Significantly different versus cluster 1.

Significantly different versus cluster 2.

Significantly different versus cluster 3.

Significantly different versus cluster 4.

Degrees of mesangial proliferation, endocapillary proliferation, interstitial inflammation, interstitial fibrosis, and arteriolar sclerosis as well as IF findings were graded using a scale of 0–3, including 0, trace (0.5+), 1+, 2+, and 3+.