Abstract:

Ｏｂｊｅｃｔｉｖｅ：To retrospectively analyze the association of linear IgG and C3 deposition with renal prognosis in patients with diabetic nephropathy.
Ｍｅｔｈｏｄｏｌｏｇｙ：Four hundred sixty patients with diabetes underwent renal biopsy and diagnosed with diabetic nephropathy according to the classification of Tervaert et al. (glomerular classes Ⅰ to Ⅲ) from 2003 to 2013 were enrolled in this study. According to kidney immunofluorescent IgG and C3 staining, they were divided into IgG (+) (n=165), IgA(-) (n=295) group and  C3 (+) (n=114), C3 (-) (n=346) group.
Ｒｅｓｕｌｔｓ：(1) No significant differences were found in age, sex, body mass index (BMI), haemoglobin, duration of kidney injury between IgG (+) and IgG (-) patients. However, IgG (+) patients suffered longer duration of diabetes, heavier urinary protein, diabetic peripheral neuropathy and diabetic retinopathy, higher levels of serum creatinine, mean arterial blood pressure, glycosylated hemoglobin, lower levels of serum albumin, serum calcium and eGFR (P<005). Interstisitial fibrosis, tubular atrophy (IFTA), interstitial inflamation and arteriosclerosis were more significant in IgG (+) group (P<005). While C3 (+) patients also had longer duration of diabetes and kidney involvement, higher levels of mean arterial blood, serum creatinine, higher prevalence of diabetic retinopathy and urinary protein (P<005). (2) In all patients, with a 5year renal survival rate was 508%, which it was 60% to 364% in IgG (+) and IgG (-) group, 535% to 43% in C3 (+) and C3 (-) group. (3) Cox proportional hazards regression analysis showed that duration of diabetes, prevalence  of diabetic retinopathy, mean arterial blood pressure, urinary protein, haemoglobin, serum albumin, serum creatinine, glycosylated hemoglobin, degree of glomerular injury, IFTA, interstitial inflammation, kidney IgG deposition and C3 deposition significantly influence renal survival. But after  adjustment for important clinical and  pathological factors, total cholesterol, glycosylated hemoglobin, urinary protein, serum creatinine, IFTA and retinopathy were the independent risk factors of renal survival.
Ｃｏｎｃｌｕｓｉｏｎ：The clinical manifestations and renal prognosis were worse in DN patients with renal IgG or C3 deposition, but neither of them was the independent risk factor of renal prognosis.