Protein S and C antigen levels in proteinuric patients: dependence on type of glomerular pathology.
The cause of the thrombotic tendency in nephrotic patients is unknown. Recent reports of thrombotic complications in patients with deficiencies of protein C or protein S (natural inhibitors of coagulation) have raised the possibility that decreased levels of these proteins may play a role in the hypercoagulable state of nephrotic patients. We measured the levels of protein C, total protein S, and free protein S antigens in 42 patients (21 nephrotic and 21 non-nephrotic) with one of four types of glomerular pathology: diabetic nephropathy (DM), focal glomerular sclerosis (FGS), membranous glomerulonephritis (MGN), and chronic renal failure due to hypertension (CRF). Protein C and total protein S antigen levels were significantly higher in FGS and MGN than they were in DM or CRF. Free protein S levels were lower in DM than they were in MGN. Protein C, total protein S, and free protein S levels did not significantly correlate with either serum albumin or degree of proteinuria. The mean levels of the three proteins did not differ between nephrotic and non-nephrotic patients. Free protein S and protein C were, however, significantly correlated (P less than .005 and P less than .002, respectively) with the type of glomerular pathology, independent of differences in age, sex, serum albumin, or degree of proteinuria. These data suggest that abnormalities of free protein S and protein C are related to the nature of the underlying renal disease, rather than to the degree of proteinuria.
Allon
M
M
Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.
Soffer
O
O
Evatt
B L
BL
Hixon
G
G
Wideman
C S
CS
D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D007674:Kidney Diseases / Q000145:classification / Q000150:complications / Q000473:pathology; D007678:Kidney Glomerulus / Q000473:pathology; D011486:Protein C / Q000097:blood*; D017293:Protein S; D011507:Proteinuria / Q000097:blood* / Q000209:etiology / Q000473:pathology; D012016:Reference Values
D006023:Glycoproteins; D011486:Protein C; D017293:Protein S