Estimated glomerular filtration rate in diabetic patients

Objective: The aim of the study is to compare estimated glomerular filtration rate (eGFR) from serum creatinine (eGFRcreatinine) and cystatine C (eGFRcystatin C) and to study the impact of these estimations on detection and staging of chronic kidney disease (CKD) in diabetic patients. Design: retrospective cross section design. Settings: Department of clinical biochemistry, Tomas Bata Hospital Inc., Zlín, Czech Republic. Materials and methods: The study population consisted of 565 consecutive diabetic patients from the outpatient diabetic clinic of Tomas Bata Hospital in Zlin in the Czech Republic. Serum creatinine and cystatin C were measured by newly standardized methods and eGFR was calculated according to Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations, which were established in 2012. CKD is defined as GFR below 1.0 ml/s/1.73m2. Results: The mean eGFRcreatinine (1.443 ± 0.014) ml/s/1.73m2 was lower than eGFRcystatin C (1.512 ± 0.017) ml/s/1.73m 2, (p < 0.002). We found poor accordance to identify CKD. The discrepancy was found in 38 patients. Conclusion: Mean eGFRcystatin C was significantly higher than eGFRcreatinine. eGFR cystatin C gives higher values than eGFRcreatinine mainly at eGFR over 1.5 ml/s/1.73m2. Our results support the use of both eGFRcystatin C and eGFRcreatinine +cystatin C in patients with diabetes mellitus without albuminuria or another marker of kidney damage at GFR stages 2 and 3a according to eGFRcreatinine