RENOGRAM DECONVOLUTION IN THE MANAGEMENT OF DIABETIC NEPHROPATHY - UTILITY OF THE MEASUREMENT OF INITIAL TRACER UPTAKE

Our objective was to assess mean transit time (MTT) and initial uptake , both parameters derived from the renal retention function (RRF), in the study of renal function in patients with diabetic nephropathy. We studied 25 patients, 7 with type I diabetes mellitus and 18 with type II diabetes mellitus, all of whom fulfilled the criteria for diabetic nephropathy with proteinuria and/or retinopathy. We found a statistica lly significant correlation between initial uptake and the other bioch emical and renographic parameters studied except proteinuria: serum cr eatinine (r = 0.66, P < 0.002), creatinine clearance (r = 0.61, P < 0. 003), glomerular filtration rate (r = 0.74, P < 0.003) and effective r enal plasma flow (r = 0.66, P,0.003). The other renographic parameters studied (maximal activity of the conventional renogram and MTT of the deconvoluted renogram) did not show any correlation. Initial uptake i s a semi-quantitative renographic parameter that can provide complemen tary information to biochemical data and it may be useful in the manag ement of diabetic nephropathy, especially in patients with high serum creatinine or creatinine clearance.