Comparison of biochemical and renal scintigraphy data before and after percutaneous nephrostomy in terms of functional reserve in upper urinary tract obstructions

Objective: This study aimed to evaluate the diagnostic value of renal scintigraphic study in upper urinary tract obstructions in comparison with biochemical data that was obtained before and after percutaneous nephrostomy (PCN).

Materials and methods: We included 30 patients (16 male and 14 female) with a mean age of 32.8 (range 5-65) years applying to our clinic between May 2004 and February 2006 with upper urinary tract obstruction. We classified patients’ kidney as nonfunctioning and poor functioning, if they had 0-9% and 10-30% function respectively, according to renal diethylenetriamine pentaacetic acid (DTPA) scintigraphy performed before PCN. After placing PCN catheter; urea, creatinine, density, and volume of the first 24-hour urine were recorded. After two weeks of follow-up, DTPA scintigraphy with diuretic was repeated. Urine biochemical and DTPA scintigraphy data obtained before and two weeks after PCN were compared.

Results: DTPA scintigraphy indicated 11 of 30 kidneys as non-functioning and 19 as poor functioning. DTPA scintigraphy performed two weeks after PCN revealed 10 of 30 kidneys as non-functioning and 20 as poor functioning. Although these figures were similar, the renal function status of 5 patients changed.

Conclusion: Although it is statistically insignificant, poor functioning upper urinary tract obstruction have a tendency to recover functionally; thus, nephrectomy should not be performed before trying PCN.