Table 4:

ROC^* analyses of lupus protein markers

	Active SLE vs. inactive SLE
Markers	AUC (95% CI)	Optimal cut-off	Sensitivity	Specificity	P-value
Axl	0.71 (0.60–0.80)	>3058 pg/ml	0.52	0.89	0.002
Ferritin	0.81 (0.70–0.90)	>27.3 ng/ml	0.62	0.88	<0.0001
IGFBP4	0.58 (0.45–0.72)	>77820 ng/ml	0.65	0.58	0.2
sTNFR2	0.60 (0.48–0.73)	>7244 pg/ml	0.40	0.89	0.13
Anti-dsDNA	0.67 (0.55–0.79)	titer ≥1:40	0.77	0.59	0.01
C3	0.79 (0.73–0.90)	<86.5 mg/dL	0.96	0.65	<0.0001
	Active renal vs. active non-renal
Markers	AUC (95% CI)	Optimal Cut-off	Sensitivity	Specificity	P-value
Axl	0.72 (0.58–0.85)	>3000 pg/ml	0.78	0.62	0.004
Ferritin	0.62 (0.47–0.77)	>94.5 ng/ml	0.41	0.99	0.007
IGFBP4	0.56 (0.41–0.72)	>275428 ng/ml	0.32	0.89	0.4
sTNFR2	0.52 (0.36–0.67)	>4761 pg/ml	0.82	0.35	0.8
Anti-dsDNA	0.55 (0.39–0.71)	titer ≥1:160	0.69	0.48	0.5
C3	0.72 (0.57–0.87)	<65 mg/dL	0.85	0.67	0.005

^*ROC = receiver operating characteristic curve; AUC = area under the curve; SLE = systemic lupus erythematosus; CI = confidence interval