Double-J stent versus percutaneous nephrostomy for emergency upper urinary tract decompression

Analysis of efficacy factors in unilateral obstructive severe renal insufficiency: a single-centre retrospective study

OBJECTIVE

To investigate the predictors of renal function recovery after treatment of severe renal impairment in unilateral upper urinary tract obstruction (UUTO).

METHODS

A retrospective analysis was conducted on 153 patients with unilateral UUTO-induced severe renal injury admitted to the First Affiliated Hospital of Chongqing Medical University from January 2014 to January 2023. Independent variables included pre-treatment estimated glomerular filtration rate (eGFR), pre-treatment 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) dynamic renal scintigraphy GFR values, C-reactive protein (CRP) levels, and body mass index. These variables were subjected to multiple linear regression analysis to predict changes in GFR (GFRd) post-treatment, with statistical significance set at P < 0.05. Categorical variables, including sex, site of obstruction, eGFR value and nephrectomy were compared with GFRd using two-sample t-tests or one-way ANOVA, with significance at P < 0.05.

RESULTS

Multiple linear regression identified a significant correlation between pre-treatment 99mTc-DTPA dynamic renal scintigraphy GFR values and CRP levels with GFRd. Female patients and those with renal pelvic obstruction exhibited a higher mean GFRd compared to males and those with ureteral obstruction, although this did not reach statistical significance.

CONCLUSION

Pre-treatment 99mTc-DTPA dynamic renal scintigraphy GFR values and CRP levels are pivotal in assessing treatment efficacy for severe renal insufficiency secondary to UUTO, with the former being indispensable for evaluating compromised unilateral renal function.

Evaluation of renovated double J stents using ureter models with and without stenosis

PURPOSE

Commercial double J stents (DJS) have a uniform shape regardless of the specific nature of various ureteral diseases. We tested renovated DJS and compared them with conventional DJS using ureter models.

METHODS

One straight ureter model included stenosis at the distal ureter near the ureterovesical junction and the other did not. We used conventional DJS and renovated 5- and 6-Fr soft DJS for ureter stones and 6-, 7-, and 8.5-Fr hard DJS for tumors. The DJS comprised holes in the upper, middle, or lower one-third of the shaft (length, 24 cm; 2-cm-diameter coils at both ends). More holes were created along the shaft based on the ureteral disease location. Conventional DJS had holes spaced 1 cm apart along the shaft. Renovated DJS had holes spaced 1 cm apart along the shaft with 0.5-cm intervals on the upper, middle, or lower one-third of the shaft. Urine flow was evaluated.

RESULTS

As the DJS diameter increased, the flow rate decreased. The flow rates of DJS with holes in the lower shaft were relatively lower than those of conventional DJS and DJS with holes in the upper and middle shafts. In the ureter model without stenosis, 6-, 7-, and 8.5-Fr renovated stents exhibited significantly higher flow rates than conventional stents. In the ureter model with stenosis, 5-, 6-, 7-, and 8.5-Fr renovated stents did not exhibit significantly higher flow rates than conventional stents.

CONCLUSION

Renovated stents and conventional stents did not exhibit significant differences in urine flow with stenosis.