Table 2

Traditional renal measures and biomarker concentrations at the time of kidney biopsy by LN activity category

Variables*(a) NIH-AI <2
(n=8)
(b) NIH-AI 2–10 (n=12)(c) NIH-AI >10 (n=12)(d) No LN
(n=47)
(abcd)
P value†
(abc)
P value
(a) versus (d)
P value
Urine biomarkers‡ and RAIL
 NGAL (ng/mL)3.19 (2.66, 3.6)3.89 (3, 4.48)3.56 (3.16, 3.78)3.59 (3.15, 3.88)0.31300.24130.2518
 Ceruloplasmin (ng/mL)8.11 (6.66, 9.5)9 (8.11, 9.64)8.62 (7.63, 9.32)3.76 (2.99, 4.98)<0.00010.6420<0.0001
 MCP-1 (pg/mL)6.34 (5.72, 7.04)7.4 (6.79, 7.87)8.33 (7.59, 8.84)5.9 (4.41, 6.92)<0.00010.01030.3518
 Adiponectin (ng/mL)4.1 (3.79, 4.51)4.84 (4.19, 5.89)6.28 (4.73, 7.1)4.8 (3.6, 5.69)0.00960.00530.1974
 Haemopexin (ng/mL)7.21 (6.64, 8.13)8.38 (7.4, 8.73)7.92 (7.54, 8.15)6.49 (6.03, 6.89)<0.00010.19300.0378
 KIM-1 (pg/mL)6.8 (5.94, 7.37)7.79 (6.71, 8.31)7.75 (6.9, 8.5)6.27 (4.93, 7.11)0.00070.18660.3771
 Urine creatinine (mg/mL)0.74 (0.62, 1.48)0.79 (0.56, 1.15)1.48 (0.74, 2.5)1.21 (0.5, 2.07)0.33440.23060.4034
RAIL score0.04 (−1.13, 1)0.69 (0.09, 1.46)2.02 (1.03, 2.68)0.21 (−1.69, 1.12)0.00270.01900.8299
RAIL-Cr score0.02 (−1.24, 1.01)0.9 (0.05, 1.45)1.83 (1.08, 2.43)0.34 (−1.5, 0.96)0.00030.01760.6849
Traditional LN measures
 SBP (mm Hg)122.5 (110, 127.5)125 (115, 136.5)122.5 (118.5, 133)118 (108, 124)0.20080.65560.5425
 DBP (mm Hg)63.5 (59.5, 77.5)77.5 (68, 89)76.5 (66.5, 87)70 (61, 75)0.10830.33010.6946
 eGFR105.5 (90, 146.5)97 (49, 128)82 (59, 133.5)109 (103, 130)0.14980.44880.5008
 UPCR1.39 (1.05, 3.79)4.49 (2.44, 9.21)2.17 (0.95, 3.83)0.14 (0.09, 0.23)<0.00010.0898<0.0001
 UACR0.12 (0.07, 0.19)0.33 (0.21, 0.48)0.63 (0.14, 2.56)0.01 (0.01, 0.02)<0.00010.0191<0.0001
 NIH-AI0.5 (0, 1)4.5 (4, 7.5)13.5 (12.5, 15)<0.0001
 NIH-CI0 (0, 0)1.5 (0, 3)1 (1, 3)0.0119
rSLEDAI score4 (2, 10)12 (12, 16)12 (8, 16)0 (0, 0)<0.00010.0058<0.0001
  • *Values are median (25th, 75th percentile).

  • †P values are generated from Kruskal-Wallis test.

  • ‡Concentration of urine proteins are natural log transformed.

  • §Standardisation by urine creatinine.

  • DBP, diastolic blood pressure; eGFR, estimated glomerular filtration rate as per modified Schwartz formula; KIM-1, kidney injury molecule 1; LN, lupus nephritis; MCP-1, monocyte chemotactic protein 1; NGAL, neutrophil gelatinase-associated lipocalin; NIH-AI, National Institute of Health activity index; NIH-CI, National Institute of Health chronicity index; SBP, systolic blood pressure; UACR, albumin-to-creatinine ratio; UPCR, urine protein-to-creatinine ratio.