Eternal dilemma between percutaneous nephrostomy and double J stenting in the management of patients with ureteral obstruction: A single center study

Ureteral obstruction is one of the most common urological emergencies, the etiology of which can be benign (in case of ureteral stones or strictures secondary to surgery) or malign (when a urothelial cancer affects the ureteral lumen or when an abdominal advanced neoplastic disease compresses the ureter '<i>ab estrinseco</i>'). To date, the most commonly used existing surgical methods for ureteral obstruction include percutaneous nephrostomy (PCN) and Double J stenting (DJS). The choose of the drainage method is multifactorial and, currently, no existing guidelines suggest to the urologist the ideal treatment for ureteral obstruction. Therefore, it was assessed which of the two main methods is superior in patients with ureteral obstruction according to normalization of renal function indices, post-operative complication and the perception of the quality of life (QoL) by the patient's point of view. In a period between 2019 and 2023, a total of 317 consecutive patients (198 males and 119 females) presenting to the emergency room of our hospital with a ureteral obstruction, which was resolved surgically by DJS or nephrostomy tube, were enrolled in the present study. All the patients signed written informed consent. Patients underwent surgical drainage when definitive treatment was not possible immediately or when a two-stage procedure was considered a safer approach. Inclusion criteria were: ureteral obstruction with fever (>38˚C), acute renal failure (indicated by an increase in creatinine and urea nitrogen blood values), risk of sepsis [suspected based on an increase in white blood cell (WBC) count] or intractable pain. Diagnosis of the ureteral obstruction was made by either a non-contrast CT and/or renal ultrasound. Specifically, 155 patients of the study sample were treated with nephrostomy, whereas 217 individuals underwent to stenting procedure. For each participant, data concerning the creatinine (mg/dl), azotemia (mg/dl), potassium (mEq/l), WBC count (10³/mm³), core temperature (˚C), pain in the side (yes or not), anti-inflammatory therapy (yes or not) and ASA score were evaluated. A Chi-square test was used to evaluate the difference in the incidence of complications according to sex and to the type of intervention. Moreover, 2-way ANOVA, considering the time (that is, pre-intervention, 2, 3, and 4 days after the intervention) as within factor and the groups as between factor, was implemented separately for the creatinine, azotemia, WBC, and body temperature values to assess differences between the PCN and DJS groups. Multiple comparisons were performed through t-tests comparing the values pre-operation and the values at two, three and four days after the intervention for each group. Moreover, independent samples t-tests were computed to identify differences between the two groups. Importantly, the multiple comparisons results were Bonferroni corrected. Finally, in order to assess a possible effect of the age on the variations of the creatinine, azotemia, WBC and body temperature for the two groups considered, a MANCOVA was performed, considering the age as a covariate. Finally, an independent sample t-test was performed between the hospitalization time of the two groups. According to our results, PCN is an improved method compared with DJS for management of ureteral obstruction in terms of renal function preservation, also ensuring an improved QoL. Moreover, PCN patients have a higher rate of post-operative complications. Then, concerning the prediction of the hospitalization time (according to the two-class classification: hospitalization time lower or higher than 3 days), the accuracy of the prediction was 61.9% for DJS and 60.2 for PCN. These results demonstrate the feasibility of predicting the hospitalization time for the patients based on their pre-drained condition. Although the results are preliminary and the accuracies are not high, this approach could help the surgeon choose the right kind of intervention for each patient.