The utility of estimation of glomerular filtration rate by serum cystatin C as a predictor of diabetic kidney disease in both type I and type II diabetic patients: a single center study

Abstract Background Diabetic kidney disease is a major microvascular complication of diabetes mellitus and is the leading cause of end-stage renal disease all over the world. The general recommendation for the subjects with DM is to perform kidney function as screening: in T1DM, 5 years after diagnosis, and in type 2, at the time of diagnosis. The early diagnosis of diabetic kidney disease depends on the albumin excretion ratio; however, the albumin excretion ratio (AER) does not correlate with the severity and progression of the disease. Methods The subjects in this study included thirty patients with type 1 diabetes mellitus and thirty patients with type 2 diabetes mellitus who were recruited from the outpatient clinic and inpatient in the Internal Medicine Department at Benha University Hospitals in the endocrinology unit from January 2022 to January 2023 as cases who were subground according to albuminuria into two groups (normoalbuminuria less than 30 mg/24 h urinary collection) and albuminuric group more than 30 mg/24 h urinary collection; all patients were subjected to thorough history including baseline characteristics, examination, and related laboratory investigations. Results Serum cystatin C level at a cutoff value of 82 was associated with sensitivity (81.4) and specificity (82.4), and it was negatively significantly correlated with BMI, duration of diabetes mellitus, albuminuria, blood urea, and serum creatinine, and it was positively significantly correlated with e-GFR creatinine. Conclusion Serum cystatin C can be used as an early marker of diabetic kidney disease in both type I and type II diabetic patients better than AER and serum creatinine.