Cystatin-C and TGF-β levels in patients with diabetic nephropathy

Abstract Objective To evaluate renal impairment in type 2 diabetic patients with normoalbuminuria or microalbuminuria by detection of serum cystatin C and serum and urinary TGF-β levels. Methods Cross-sectional study conducted at the Department of Endocrinology in Baskent University School of Medicine. Patients with type 2 diabetes mellitus without known overt diabetic nephropathy were included in the study. Recruited patients were stratified into four groups, matched in terms of age, gender, microalbuminuria level and estimated GFR calculated with MDRD. Results 78 patients were enrolled. They were categorized into four groups depending on their urinary albumin excretion and estimated glomerular filtration rate. Macrovascular complication was found to be higher in patients with microalbuminuria than in other patients ( p r  = −0.892, p r  = −0.726, p  = 0.001). Conclusions Although urinary albumin excretion is recommended for the detection of type two diabetic nephropathy, there is a group of patients with decreased eGFR but without increased urinary albumin excretion, in which serum cystatin C level was indicated to be used as an early biomarker of diabetic nephropathy.