Abstract:

Objective: To compare plasma antithrombin III (ATIII) concentration and related factors in adult nephrotic syndrome patients with different histological patterns. Methodology: Seventy-two adult nephrotic syndrome patients with different histological patterns were enrolled in this study. They were minimal change disease (MCD, n=26), focal segmental glomerulosclerosis (FSGS, n=26) and membranous nephropahty (MN, n=20). 20 healthy adults served as normal control. The blood and urinary samples were collected before renal biopsy. The levels of plasma and urine ATIII were detected by immune rate nephelometry. The clinical characteristics at biopsy, plasma and urinary ATIII were compared. The factors related to plasma ATIII were analyzed by Person、Spearman methods, followed by multi-linear regression. Results: The levels of serum albuminin, creatinine, total cholesterol, IgG and proteinuria at biopsy in MN group were significantly different from FSGS and MCD group (P<0.05). The difference of these variables were not significant between FSGS and MCD group P>0.05）. The levels of urinary C3, α2 macroglobulin，N-acetyl-β-D-glucosaminidase，and retinol binding protein in FSGS group were higher than those in MCD and MN group (P<0.05). The plasma level of ATIII concentration in FSGS and MCD were 15.64±3.86mg/dL and 18.10±4.8mg/dL (P<0.05) , respectively, which were less than that in MN (28.08±4.23mg/dL). The plasma level of ATIII was decreased in 26 cases (100%) of MCD, 23 (88.4%) of FSGS and 3 (15%) of MN (P<0.05). The level of urinary ATIII was increased in 8 cases of 20 FSGS, 4 of 22 MCD and none of MN (P <0.05). The plasma ATIII in FSGS group was correlated with serum albumin positively (r=0.559, P<0.01), and proteinuria negatively (r=-0.505, P<0.05). Similarly, the plasma ATIII in MCD group was correlated with serum albumin ( r=0.564，P<0.05) and IgG (r=0.529, P<0.05) positively, and proteinuria (r=-0.429, P<0.05) negatively. Multi-linear regression showed that serum albumin was an independent factor in both FSGS and MCD with decreasing plasma ATIII (R² ＝0.312，0.320，P<0.05）. During the follow-up, two FSGS patients with lower ATIII concentration had venous thrombosis attack. Conclusion：The level of plasma ATIII in patients with nephrotic syndrome was related to the underlying renal diseases. The plasma ATIII concentration was much lower in FSGS and MCD than that in MN, which may be secondary to the differential urinary loss.