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Infected obstructed ureteric stone in a solitary kidney — MSRA MCQ

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HardUrologyInfected obstructed ureteric stone in a solitary kidneyMSRA

A 63-year-old man is assessed in a same-day urgent care service with 12 hours of severe left-sided colicky flank pain, rigors and vomiting. He has a solitary functioning left kidney following right nephrectomy after trauma. He is febrile (38.5°C), heart rate 108/min and blood pressure 112/68 mmHg. Urine dipstick is positive for nitrites, leucocytes and blood. His creatinine is 165 micromol/L (baseline 82 micromol/L). Low-dose non-contrast CT performed earlier today shows an 8-mm proximal left ureteric calculus with moderate hydronephrosis. What is the most appropriate next step?

Educational content. Not a substitute for clinical judgement or local policy.

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Correct answer: A — Arrange immediate hospital transfer for urological assessment and urgent upper-tract decompression with intravenous antibiotics

Explanation lettering: C = shown as A · E = shown as B · D = shown as C · B = shown as D · A = shown as E

This is an infected, obstructed upper urinary tract in a solitary functioning kidney, with acute kidney injury. The fever, rigors, nitrite-positive urine and tachycardia indicate urinary infection; CT confirms obstruction, and the creatinine rise demonstrates a complication of that obstruction. This requires immediate urological involvement for drainage (ureteric stent or nephrostomy) alongside intravenous antibiotics. Antibiotics without drainage are inadequate where infected urine is trapped above an obstruction. A is inappropriate because oral outpatient treatment risks rapid deterioration to urosepsis and does not relieve obstruction. B is initially plausible because he requires intravenous antibiotics and monitoring, but medical admission alone delays the required urological source control. D is too slow: definitive stone treatment can follow stabilisation, whereas urgent decompression is required now. E would be reasonable only for selected uncomplicated distal ureteric stones under conservative management; infection, hydronephrosis, AKI and a solitary kidney are major exclusions.

Reference: NICE NG148: Acute kidney injury: prevention, detection and management — relieving urological obstruction (2019) — https://www.nice.org.uk/guidance/ng148/chapter/Recommendations NICE NG118: Renal and ureteric stones: assessment and management — overview (Published 2019; last reviewed 2021) — https://www.nice.org.uk/guidance/ng118 NICE NG118: Renal and ureteric stones: assessment and management — diagnostic imaging and pain management (2019) — https://www.nice.org.uk/guidance/ng118/chapter/Recommendations