Undiagnosed Kidney Injury in Uninsured and Underinsured Diabetic African American Men and Putative Role of Meprin Metalloproteases in Diabetic Nephropathy

Table 2

Biomarkers of kidney injury in diabetic patients with no known kidney disease, nondiabetic controls, and diabetics with diagnosed kidney disease. DM: diabetes mellitus; DKD: diabetic kidney disease; KIM-1: kidney injury molecule-1; NGAL: neutrophil gelatinase-associated lipocalin; MCP-1: monocyte chemoattractant protein-1; Q3: upper quartile; IQR: interquartile range.

Biomarker	Plasma KIM-1; (pg/ml)	Urine KIM-1; (μg/g Cr)	Plasma cystatin C; (μg/ml)	Urine cystatin C; (ng/g Cr)	Plasma NGAL; (ng/ml)	Urine NGAL; (ng/g Cr)
Range of nondiabetic group	(7.78, 63.44)	(0.16, 1.23)	(0.49, 1.21)	(5.29, 82.72)	(5.98, 76.64)	(0.43, 26.57)
Mean ± SD	30.39 ± 17.97	0.47 ± 0.30	0.87 ± 0.20	27.45 ± 20.74	41.75 ± 18.24	5.84 ± 5.71
>mean + 2SD in DM versus in DKD	52% versus 100%	23% versus 20%	17% versus 78%	19% versus 64%	17% versus 40%	24% versus 73%
>mean + 3SD in DM versus in DKD	45% versus 80%	12% versus 20%	11% versus 78%	14% versus 64%	13% versus 40%	21% versus 64%
Q3 ± IQR	46.56 ± 29.62	0.54 ± 0.31	0.97 ± 0.22	27.75 ± 11.95	55.44 ± 27.40	7.55 ± 5.04
>Q3 + 1.5 IQR in DM versus in DKD	40% versus 80%	25% versus 27%	17% versus 78%	43% versus 79%	13% versus 40%	24% versus 73%
>Q3 + 3 IQR in DM versus in DKD	24% v. 70%	10% versus 20%	11% versus 78%	21% versus 64%	6% versus 30%	21% versus 64%