Determination of the glomerular filtration rate in patients with type 2 diabetes: an assessment of the agreement between 51 Cr-EDTA plasma clearance and 99m Tc-DTPA plasma clearance, 99m Tc-DTPA renography and plasma creatinine prediction equation.

•Lack of robust evidence on 51Cr-EDTA and 99mTc-DTPA plasma clearance agreement.•Renographic Gates’ method and serum creatinine equations are used for GFR measurement.•In comparative studies patients with diabetes are under-represented or missing.•A close agreement is shown between 51Cr-EDTA and 99mTc-DTPA plasma clearance.•99mTc-DTPA plasma clearance can replace 51Cr-EDTA in patients with type 2 diabetes.•Renographic Gates’ method and the CKD-EPI equation cannot assess GFR reliably.