Clinical Outcomes of Internal Ureteral Stents versus Image-Guided Percutaneous Nephrostomy Tubes for the Management of Pyonephrosis: A Propensity Score Matched TriNetX US Collaborative Network Study

Purpose: To analyze outcomes following internal ureteral stents compared to percutaneous nephrostomy tubes among propensity score matched patients with pyonephrosis.

Materials and Methods: An IRB exempt query was conducted through a large multi-institutional deidentified database for patients with pyonephrosis (ICD-10DM N13.6). Patients with a history of cystectomy, nephroureteral catheter, and pregnancy at the time of interest were excluded. The internal ureteral stent (IUS) cohort required the CPT code 50433. The image-guided percutaneous nephrostomy (PCN) tube cohort was identified as having CPT code 50432, SNOMED 31327000, and SNOMED 21904006. Propensity score matching was conducted for demographics, hydronephrosis, uroslithiasis, acute kidney injury, INR, WBC count, platelet count, and BMI.

Results: Following propensity score matching, 16,128 patients were identified in both the PCN and IUS cohorts with the average age being statistically higher among IUS patients (63.4±17.2 vs. 62.8±17.3; p = 0.01). Preoperative INR, WBC count, platelet count, BMI, and all other patient demographics were not statistically different.

Analysis of 30 day post-intervention data found IUS patients to have a lower risk of mortality (4.4% vs. 6.6%; Risk Difference (RD): 2.2%; p < 0.0001), all-cause sepsis (23.2% vs. 27.1%; RD: 3.8%; p < 0.0001), and emergency or inpatient revisit (41.7% vs. 48.3% RD: 6.6%; p < 0.0001). Post-intervention laboratory findings found IUS patients to have a lower creatinine (mean±STD; p-value) (1.37±1.08 vs 1.42±1.17; p < 0.0001), while PCN patients were found to have a lower INR (1.28±0.48 vs. 1.32±0.53; p < 0.0001) and WBC count (13.16±112.52 vs. 17.82±188.69; p = 0.03).

Conclusion: This propensity score-matched study identified that IUS provides a safer approach to the management of patients with pyonephrosis with lower rates of mortality, all-cause sepsis, and revisits following the intervention along with labs trending towards normal ranges within 30 days postoperatively.