Case Report and Literature Review —Successful Single-Stage Retrograde Ureteroscopy for an Extreme Localized Burden of over 1000 Ureteral Micro-Calculi

Abstract

Background : Obstructive ureterolithiasis typically manifests as a single or limited number of migrating renal calculi. An accumulation of over a thousand individual, distinct micro-calculi isolated entirely within a single ureter represents an extreme case of primary steinstrasse -like obstruction without a preceding history of shockwave lithotripsy. Managing such a severe localized stone burden poses clear clinical challenges regarding mucosal preservation, operative duration, and stone-free clearance rates (SFR). Case Presentatio n : A 56-year-old male with an E. coli urinary tract infection—pre-treated with targeted antibiotics—presented with acute left lumbar colic indicative of severe upper tract obstruction. Radiological workup identified a continuous column of tightly packed 2 - 3 mm micro-calculi and occasional 5 - 6 mm stones spanning from the vesicoureteral junction (VUJ) to the mid and upper ureter, alongside multiple ipsilateral renal calculi. The patient underwent an urgent, single-stage retrograde semirigid transurethral ureteroscopy (URS). A total stone burden estimated at over 1000 individual micro-calculi was successfully cleared using a manual volumetric sampling extraction technique combined with endoscopic suction. Conclusion : Complete endourological clearance was achieved without mucosal avulsion, urosepsis, or secondary complications. The patient was safely discharged in excellent clinical condition, demonstrating that single-stage endourological extraction via a semirigid scope remains highly effective even when facing an extreme localized physical count of stones.