Primary Versus Delayed Ureteroscopy for Obstructing Ureteric Calculi: A Systematic Review and Meta-analysis from the European Association of Urology Endourology.

BACKGROUND AND

OBJECTIVE

Primary ureteroscopy (URS; P-URS) for obstructing ureteric stones involves emergent stone retrieval within 24-48 h of acute presentation. We compared the effectiveness of P-URS versus delayed URS (D-URS) for noninfected obstructing ureteric stones.

METHODS

A systematic review was conducted using PubMed, Embase, Cochrane Library, and Scopus from database inception up to October 2025. Studies comparing P-URS with D-URS were eligible. Primary outcomes were stone-free rate (SFR) and complications. Secondary outcomes included retreatment, sepsis, stent use, readmissions, and costs. Random-effects meta-analysis and meta-regression were performed for prespecified study-level moderators.

KEY FINDINGS AND LIMITATIONS: Fifteen studies involving 19 907 patients were included. Pooled SFR in P-URS was 89% (confidence interval [CI] = 80-95) and D-URS 87% (CI = 77-94). There was no statistically significant difference in SFR between P-URS and D-URS in an all-studies meta-analysis (odds ratio [OR] 1.20; 95% CI = 0.75-1.92; p = 0.5) with substantial heterogeneity (I2 = 86%). In a subgroup of five studies using a zero-fragmentation definition on any postoperative imaging modality (radiographic zero fragment rate [ZFR]), P-URS was associated with higher odds of stone-free status (OR 1.49, 95% CI = 1.10-2.02, I2 = 0%). Sensitivity analysis restricted to two computed tomography (CT)-based trials (strict ZFR) showed a larger effect (OR 1.95, 95% CI = 1.19-3.19, I2 = 0%). Complications and secondary outcomes did not differ materially between approaches. Limitations include methodological heterogeneity, predominantly retrospective designs, and sparse data using strict ZFR definitions.

CONCLUSIONS AND CLINICAL IMPLICATIONS: P-URS appears to be a feasible option for selected patients with noninfected obstructing ureteric stones without large overall differences in SFR or complication rates compared with D-URS. In radiographic and strict CT-based ZFR subgroups, P-URS shows modestly higher SFRs, but these signals arise from few studies and should be considered hypothesis generating. Future research should incorporate contemporary technology, patient-reported outcomes, and formal cost-effectiveness analyses.