Renal function reserve in patients with early type 2 diabetic nephropathy using protein loading-scintirenography / 中华核医学杂志

ABSTRACT

Objective To explore a sensitive method and index to evaluate renal functional reserve (RFR) in patients with early diabetic nephropathy (DN) using protein loading-scintirenography.Methods Fifty subjects were studied and divided into 3 groups.Group one (G1) consisted of 14 healthy volunteers;Group two (G2) consisted of 15 patients with type 2 diabetes mellitus (DM) and normoalbuminuria; Group three (G3) consisted of 21 patients with type 2 DM and microalbuminuria.All subjects underwent baseline and protein loading-99 Tcm-DTPA scintirenography within one week.RFR was calculated as the difference between stimulated and baseline glomerular filtration rate (GFR), time of peak ( Tb ), time of half excretion ( C1/2 ), residual rate at 20 min ( C20/b ) .Variance analysis and t-test were used to analyze the group differences.Results ( 1 ) The RFR in terms of GFR had statistical difference between any two groups (t=14.884, 32.180, 16.042, all P＜0.01).After protein-loading, the GFR of G1, G2 and G3 increased 20.1, 10.9 and 2.2 ml·min-1·1.73 m-2 respectively.Therefore, the RFR decreased before microalbuminuria in type 2 DM patients.(2)There was statistical difference between the RFR of G1 and G2 in terms of C1/2 (t = 5.505, P＜0.05 ), and between G1 and G3 ( t = 8.914, P＜0.01 ).(3) There was statistical difference of the RFR in terms of TP between G1 and G3 (t = 5.690, P ＜ 0.01 ).(4) There was statistical difference of the RFR in terms of C20/b between G1 and G3 (t= 4.376, P＜0.05 ).Conclusions 99Tcm-DTPA protein loading-scintirenography is an effective method for measuring RFR to evaluate early DN in type 2 DM patients.