A 52-year-old woman with a history of recurrent calcium oxalate kidney stones presents with acute left flank pain and hematuria. Non-contrast CT KUB reveals a 15 mm stone in the left mid-ureter with moderate hydronephrosis. Serum creatinine is 1.8 mg/dL (baseline 1.0 mg/dL), and she is afebrile. Urine culture is pending. She has severe pain uncontrolled by NSAIDs and intravenous fluids. What is the most appropriate next step in management?

Explanation

## Management of Complicated Ureteric Stone with Renal Dysfunction ### Clinical Assessment This patient has multiple indicators for active intervention: - **Stone size:** 15 mm (>10 mm) with low spontaneous passage rate (<20%) - **Renal dysfunction:** Creatinine rise from 1.0 to 1.8 mg/dL indicates obstruction-induced renal impairment - **Moderate hydronephrosis:** Significant obstruction - **Failed conservative management:** Uncontrolled pain despite NSAIDs and hydration - **No fever/sepsis:** Rules out infected obstructed system (which would require urgent percutaneous decompression) ### Why Ureteroscopy Is Indicated **High-Yield:** Ureteroscopy is the gold-standard first-line intervention for ureteric stones in non-infected, non-septic patients with: - Stones 10–20 mm - Renal dysfunction from obstruction - Failed conservative management - Uncontrolled symptoms ### Ureteroscopy Technique 1. **Rigid or flexible scope** depending on stone location (mid-ureter: either can be used) 2. **Laser lithotripsy** (holmium:YAG laser) for fragmentation and disintegration 3. **Stone basketing** for smaller fragments 4. **Ureteric stent placement** post-operatively if ureteral trauma, residual fragments, or significant edema **Clinical Pearl:** Holmium:YAG laser is the preferred energy source for all stone compositions (calcium oxalate, uric acid, struvite, cystine) with minimal urothelial injury. ### Why NOT Percutaneous Nephrostomy Percutaneous nephrostomy is reserved for: - **Infected obstructed systems** (fever + obstruction = urological emergency) - **Solitary kidney** with obstruction and renal failure - **Failed ureteroscopy** or anatomical contraindications to ureteroscopy This patient is afebrile with no sign of infection, so percutaneous decompression is not the immediate priority. ### Why NOT Conservative Management - Stone >10 mm has <20% spontaneous passage rate - Worsening renal function (creatinine 1.8 mg/dL) indicates progressive obstruction - Uncontrolled pain despite maximum medical therapy **Key Point:** Renal function deterioration is a strong indication to intervene, as prolonged obstruction risks permanent nephron loss. [cite:Campbell-Walsh Urology 12e Ch 48]