Can Renal Blood Flow, Glomerular Filtration Rate or ^99mTc‐DMSA Uptake Predict Outcome in Experimental Unilateral Renal Obstruction?

Abstract

Single kidney glomerular filtration rate (SK GFR), single kidney blood flow (SK BF) and differential renal function (DRF), using both technetium labelled diethylene-pentaacetic acid (99mTc-DTPA) and dimercaptosuccinic acid (99mTc-DMSA), were examined as predictors of outcome in a pig model of complete unilateral ureteric obstruction. SK GFR and SK BF were unable to predict outcome following relief of obstruction but there was a high curvilinear correlation between DRF assessed at the end of defined periods of obstruction and after relief of obstruction using 99mTc-DMSA. Functional recovery was near complete using DMSA when the loss in DRF did not exceed 30%, after which there was an exponential decline in expected recovery. There was no difference between DRF using 99mTc-DTPA or 99mTc-DMSA in controls or before or after obstruction but significant differences between assessment by these radionuclides existed in the obstructed kidney at 24 h, 5 days, 10 days and 20 days. 99mTc-DMSA is a sensitive agent in the prediction of outcome following acute complete obstruction in the pig but its assessment of DRF in the obstructed kidney differs markedly from that of 99mTc-DTPA.

Predictive value of renal histological changes for postoperative renal function improvement in children with congenital ureteropelvic junction stenosis

“…However, it is well known that a radiological technician computes DRF and the value is subject to variability, depending on where the outlined regions of interest are drawn. [13][14][15] Apart from radionuclide assessment, some biochemical markers in the urine have been proposed to help determine whether a hydronephrotic kidney requires surgery or can be safely monitored without fear of parenchymal damage. Various biochemical indicators of the response of the kidney to obstructive damage have been investigated, and some of them have clinical promise.…”

“…10,11 However, it is well known that differential functional renal (DRF) activity computed by a radiology technician and its value is subject to extreme variability, depending on where the evaluated regions of interest are drawn. [12][13][14][15] Levels of biochemical markers, such as certain enzymes and microproteins, in urine obtained from obstructed renal units may have a role in predicting the final outcome of corrective surgery in patients with apparent uretero-pelvic obstruction. However, studies have shown that the biochemical markers have limited application and reliability because of extremely variable results.…”