PassFinals
Renal & Urology

Renal colic and ureteric stones

A ureteric stone causes severe colicky loin-to-groin pain by obstructing urine flow and triggering ureteric spasm; fever, anuria, renal impairment or a solitary kidney changes this into an urgent urological pathway.

In a nutshell

A ureteric stone causes severe colicky loin-to-groin pain, often with vomiting and haematuria. Confirm suspected adult renal colic with urgent low-dose CT, use an NSAID first-line when safe, and remember that fever, anuria, AKI, bilateral obstruction or a solitary kidney makes this an urgent urological pathway.

Classic presentation

A restless patient with sudden severe unilateral loin pain radiating towards the groin, nausea or vomiting and possible haematuria.

Key points

  • Colicky visceral pain makes patients restless; peritonitis usually makes them still and guarded.
  • CT is the urgent first-line adult imaging test; use ultrasound first-line in pregnancy and children.
  • An infected obstructed kidney needs antibiotics, resuscitation and urgent drainage with a stent or nephrostomy; analgesia alone is unsafe.
  • Small stones may pass, but size, location, pain, renal function, infection, pregnancy and solitary-kidney status determine the pathway.
  • NSAIDs are first-line analgesia when safe; intravenous paracetamol and then opioids are escalation options, and antispasmodics are not routinely offered.
  • Persistent intolerable pain or unlikely passage requires timely urological treatment rather than repeated emergency analgesia.
  • Every stone episode is an opportunity for stone analysis, serum calcium, dietary advice and recurrence prevention.

First-line investigation

Urgent low-dose non-contrast CT KUB for adults; ultrasound first-line in pregnancy and children, with urine, renal-function and infection assessment.

Management

Analgesia and danger assessment

  • Give an NSAID when safe, assess for sepsis, AKI, anuria, bilateral or solitary-kidney obstruction, pregnancy and dangerous mimics, and involve urology early when any red flag is present.1,3,4

Image and classify the obstruction

  • Arrange urgent low-dose CT for adults or ultrasound first-line for pregnancy and children; document stone size, location, hydronephrosis, renal function and evidence of infection.1,5,3

Support safe passage

  • Use antiemetic and appropriate fluid support, provide safety-netting and observe only when pain, renal function, infection status and the likelihood of passage are safe.1,2,6

Treat infection or failed passage

  • Drain an infected or high-risk obstruction urgently with a ureteric stent or nephrostomy plus antibiotics and sepsis care; arrange definitive stone treatment promptly when pain is intolerable or passage is unlikely.1,3,4

Prevent recurrence

  • Send a retrieved stone for analysis where possible, check serum calcium, discuss fluid and dietary measures and use specialist or BNF guidance for potassium citrate or other prevention when indicated.1,2,6

Exam traps

  • Fever or rigors with obstruction is not uncomplicated renal colic: treat as possible infected obstruction and obtain urgent urological source control.
  • A normal urine dip does not exclude a stone.
  • Do not use routine antispasmodics for renal colic.
  • Do not use alpha-blockers as a blanket medical-expulsive treatment; NICE limits the adjunctive role to selected adults having SWL for small ureteric stones.
  • Do not delay intervention for an obstructed solitary kidney, bilateral obstruction, anuria, AKI or uncontrolled pain.
  • A pulsatile abdominal mass, shock, peritonism or pregnancy requires a parallel dangerous-mimic pathway.

Illustrations

Ureteric obstruction and referred painDiagram of the ureter and its narrowing points showing how a migrating stone produces loin-to-groin pain, hydronephrosis and bladder irritation near the vesicoureteric junction.PassFinals · original
A ureteric calculusClinical image of a passed renal calculus used to connect the physical stone with the sudden colicky loin-to-groin pain of ureteric obstruction.Robert R. Wal, Wikimedia Commons · Public domain
Hydronephrosis proximal to a stoneUltrasound image showing a dilated renal pelvis and calyces upstream from ureteric obstruction, with an accompanying warning that infection, AKI or a solitary kidney requires urgent urological escalation.Kristoffer Lindskov Hansen, Michael Bachmann Nielsen and Caroline Ewer, Wikimedia Commons · CC-BY-4.0

Key sources

  1. NICE NG118: Renal and ureteric stones—assessment and management, including May 2026 update (NICE recommendations for urgent imaging, analgesia, stone-size treatment pathways, 48-hour surgery, stone analysis, serum calcium, prevention and the statement that infected obstruction needs urgent drainage.)
  2. NHS: Kidney stones (Current NHS symptom and safety-netting information, including severe pain, fever or shivering, haematuria and the risk of infection or kidney dysfunction.)
  3. NICE NG148: Acute kidney injury—prevention, detection and management (NICE pathway for suspected pyonephrosis, obstructed solitary kidney, bilateral obstruction and urgent urological decompression in AKI.)
  4. British Association of Urological Surgeons: Renal tract stones and colic (UK urological emergency guidance for infected obstruction, urgent drainage, sepsis care, admission risks and acute ureteric colic.)
  5. NICE QS195: Renal and ureteric stones quality standard (NICE quality statements supporting CT timing, first-line NSAID analgesia, serum calcium and 48-hour surgery where pain is not tolerated or passage is unlikely.)
  6. BNF online: current prescribing information for renal-colic analgesia, alpha-blockers and stone-prevention medicines (Use current BNF and local urology or renal protocols for renal adjustment, pregnancy, contraindications, interactions, dosing and monitoring; no fixed medication dose is reproduced here.)

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.