Abstract:

ABSTRACT  Objective: To investigate the clinical and histological risk factors and to predict the progression to macroalbuminuria, remission to normoalbuminuira and eGFR decline in type 2 diabetic patients with microalbuminuria. Methodology: Sixty one type 2 diabetic patients with MAU (urinary albumin excretion 30~300mg/24h) and serum creatinine ≤1.24mg/dl who received renal biopsy were enrolled in this study. The clinical data such as baseline age, duration of diabetes mellitus, blood pressure, smoking history, ACEI/ARB prescription, serum creatinine, eGFR, serum lipid, HbA1c, urinary albumin, NAG and RBP were recorded. The histological data including the percentage of global sclerosis, glomerular volume, mesangial area ratio, glomerular basement membrane width, podocyte foot process width, slit diaphragm frequency were also measured. eGFR rapid decline was defined as a rate of eGFR loss of ≥3.3% per year. Results: 54 patients were included for analyzing, and 7 patients were lost during follow-ups. 40.7% (22/54) patients progressed to macroalbuminuria, 46.3% (25/54) were stable and 13.0% (7/54) were remission to normoalbuminuria. The urinary albumin at baseline was lower in remission group than that in progression and stable groups（103.05±53.88 vs 139.58±76.88 vs 192.58±97.64mg/24h，P=0.025）, and the SD frequence was higher in remission group than that in other two groups. Multivariate COX regression analysis indicated that SD frequence and glomrular volume were independent predictors of progression to macroalbuminuria, and DM duration, serum uric acid, cholesterol and ACEI/ARB prescription were independent infect factors of remission to normoalbuminuria. Multivariate Logistic regression analysis indicated that lower baseline eGFR and higher serum uric acid concentration were the independent predictors of eGFR decline in this cohort. Conclusion: Multiple clinical and histological indices can predict the progression and remission of MAU in type 2 diabetic nephropathy, and baseline eGFR and serum uric acid concentration can predict the decline of eGFR.

Key words: diabetic nephropathy, microalbuminuria, renal histological injury, GFR, risk factors