Introduction:
Obstructive pyelonephritis is a urological emergency with high morbidity and mortality. The initial treatment is urgent urinary drainage (double-J stent or percutaneous nephrostomy) combined with intravenous antibiotics to control infection and stabilize the patient. After sepsis resolution, stone removal is essential to prevent recurrence. Flexible ureterorenoscopy (RIRS) with Holmium laser has emerged as a minimally invasive option.
Methods:
This narrative review summarizes evidence from observational studies and clinical trials on the safety, efficacy, and timing of RIRS following urinary drainage in patients with obstructive pyelonephritis. Literature was searched in PubMed, Scopus, Embase, and Google Scholar until 2025 using relevant keywords. Eligible studies reported RIRS outcomes, including stone-free rate (SFR), complications, renal function recovery, and timing after infection control.
Results:
Most studies recommend performing RIRS 2–4 weeks after drainage, once fever resolves, inflammatory markers normalize, and urine culture is sterile. Reported SFR ranges from 80–90% after a single session for stones <2 cm, with additional procedures further improving outcomes. Postoperative complications are generally mild (Clavien I–II), with fever being the most common (5–10%). Severe complications such as sepsis or major bleeding are rare (<2%). Compared with PCNL, RIRS shows lower bleeding risk and shorter hospitalization, making it suitable for high-risk patients or those needing rapid recovery.
Conclusion:
RIRS is a safe and effective treatment option for stone clearance after obstructive pyelonephritis once infection is controlled. Optimal timing is typically within 2–6 weeks post-drainage, individualized based on clinical and microbiological recovery.