A 38-year-old man presents to the emergency department with acute onset left flank pain radiating to the groin, associated with nausea and vomiting. He has a history of recurrent kidney stones. On examination, he is restless and diaphoretic. Vital signs: BP 128/82 mmHg, HR 102/min, RR 18/min. Urinalysis shows hematuria (3+) and crystalluria with calcium oxalate crystals. Non-contrast CT abdomen-pelvis (NCCT) confirms a 7 mm stone in the left proximal ureter with mild hydronephrosis. Serum creatinine is 1.0 mg/dL and urine culture is sterile. What is the most appropriate immediate management?

Explanation

## Clinical Context This patient presents with acute ureteric colic from a small (7 mm) ureteric stone with preserved renal function and no signs of infection or obstruction-related sepsis. ## Management Principles for Ureteric Stones **Key Point:** Stone size is the primary determinant of spontaneous passage rates. Stones <6 mm have ~90% passage rate; 6–10 mm have ~50% passage rate; >10 mm have <10% passage rate [cite:Urology textbook]. **High-Yield:** The 7 mm stone in this patient falls into the intermediate category with reasonable expectation of spontaneous passage, especially with appropriate conservative management. ### Conservative Management Protocol 1. **Analgesia:** NSAIDs (indomethacin 50 mg BD) or opioids for pain control 2. **Hydration:** Maintain urine output 2–3 L/day to facilitate stone passage 3. **Observation:** Serial imaging (ultrasound or repeat NCCT) at 2–4 weeks 4. **Medical expulsive therapy (MET):** Alpha-blockers (tamsulosin 0.4 mg OD) improve passage rates by 30–40% **Clinical Pearl:** Restlessness and diaphoresis are typical of acute colic and do not indicate need for immediate intervention; they reflect pain severity, not stone-related complications. ### When to Escalate to Intervention - Stone >10 mm - Fever with obstructed infected system (pyonephrosis) → **urgent decompression** - Solitary functioning kidney with complete obstruction - Recurrent obstruction or failure to progress after 4–6 weeks - Intractable pain or vomiting preventing oral intake This patient has none of these indications. ## Why Conservative Management is Optimal Here - Sterile urine (no infection) - Normal renal function (Cr 1.0 mg/dL) - Mild hydronephrosis only - Stone size 7 mm (intermediate, ~50% spontaneous passage) - Hemodynamically stable **Mnemonic: STONE-PASS** — **S**mall (<6 mm), **T**ime (allow 4–6 weeks), **O**bservation (serial imaging), **N**o infection, **E**xpulsive therapy (alpha-blockers); **P**ain control, **A**deq hydration, **S**erial follow-up, **S**urgery only if failure.