Does it need treatment?
Not every stone needs an operation. Stable, uncomplicated stones can sometimes be observed, while selected ureteric stones may pass naturally.
Kidney stones · ureteric stones · RIRS
The right stone treatment depends on more than stone size.
Location, number, density, obstruction, infection, kidney anatomy, likelihood of passage and patient factors all influence whether a stone should be observed, treated endoscopically or approached through the kidney.
Is there infection or obstruction?
Fever, sepsis, impaired drainage or threatened kidney function can change the priority from routine stone treatment to urgent drainage and infection control.
Choose the route, not just the technology
SWL, ureteroscopy, RIRS and PCNL differ in invasiveness, clearance, need for repeat procedures and suitability for the stone anatomy.
Symptoms
What symptoms and problems can kidney or ureteric stones cause?
Stone symptoms depend strongly on location and obstruction. A stone in the ureter behaves differently from a non-obstructing stone sitting inside the kidney.
Renal colic
Severe pain in the side or back, often radiating toward the lower abdomen or groin.
Blood in urine
Visible or microscopic haematuria can accompany stones, although other causes may need consideration.
Nausea and vomiting
Acute ureteric obstruction commonly produces significant gastrointestinal symptoms.
Urinary symptoms
Frequency, urgency or burning may occur, especially with a stone lower in the ureter.
Recurrent infection
Some stones coexist with urinary infection and may contribute to repeated episodes.
No symptoms at all
Some kidney stones are found incidentally and still need assessment for growth, obstruction and future risk.
Fever with an obstructing stone needs urgent assessment.
Fever or chills with obstruction can indicate an infected obstructed urinary system. Severe illness, persistent vomiting or reduced urine output should not wait for a routine appointment.
Evaluation
Before choosing a procedure, define the stone burden and the urinary tract.
The written scan report is useful, but treatment planning often depends on seeing the images and understanding the stone position, anatomy and drainage.
ImagingUltrasound or CT defines location, size, number, anatomy and obstruction. CT density may help predict how a stone will respond to SWL.
Urine testingUrinalysis and urine culture are important when infection is suspected or intervention is planned.
Kidney functionBlood tests help assess renal function, especially with obstruction, infection or bilateral stone disease.
Previous stone historyPrior procedures, stents, stone composition and recurrence pattern can influence the current plan.
Patient factorsMedical conditions, medications, anatomy, pregnancy status, occupation and travel plans can all affect timing and treatment choice.
Treatment choices
The aim is reliable stone clearance with the lowest appropriate treatment burden.
More invasive treatment is not automatically better, and the least invasive option is not always the most efficient. The trade-off is different for every stone.
Observation / passage
Suitable for selected uncomplicated stones when spontaneous passage or safe surveillance is reasonable and follow-up is reliable.
Shock-wave lithotripsy (SWL)
Uses externally generated shock waves to fragment selected stones. Success depends on size, location, density, body habitus and anatomy.
Ureteroscopy (URS)
An endoscope is passed through the urinary passage into the ureter. Stones can be fragmented with laser and removed where appropriate.
RIRS
Flexible ureteroscopy inside the kidney. It allows direct visualisation and laser treatment of many renal stones without a skin incision.
PCNL
Accesses the kidney through a tract from the back and is generally the most efficient option for large or complex renal stone burdens.
Where RIRS fits
RIRS is useful for many renal stones—but not every stone burden.
For larger or complex stones, PCNL may achieve clearance more efficiently. For favourable smaller stones, SWL may avoid endoscopy. The choice should reflect the stone rather than a preference for one technology.
RIRS may fit well
Many small-to-moderate renal stones, selected lower-pole stones, stones less suitable for SWL and patients where avoiding a percutaneous tract is desirable.
PCNL may be more efficient
Large stone burdens, staghorn or complex stones, and situations where achieving substantial clearance in one treatment is particularly important.
Staging is sometimes sensible
For selected larger stones treated with RIRS, more than one session may be needed. That possibility should be discussed before treatment rather than treated as a surprise afterwards.
RIRS, PCNL and SWL
How do the basic principles differ?
Read the dedicated RIRS vs PCNL comparison →
This is a simplified comparison. Exact suitability depends on stone anatomy, infection, kidney function, medical factors, equipment and surgeon experience.
| Feature | RIRS | PCNL | SWL |
|---|---|---|---|
| Access | Through natural urinary passage | Through a tract into the kidney | No endoscope or tract; shock waves from outside the body |
| Skin incision | No | Small puncture / incision | No |
| Typical strength | Many renal stones with endoscopic access | Large or complex stone burdens | Selected favourable stones |
| Repeat treatment | May be needed with larger burdens | May be needed in complex disease | Multiple sessions can be required |
| Selection depends on | Size, location, number, density, anatomy, infection, obstruction, prior surgery and patient factors | ||
Ureteric stents
A stent is a temporary drainage tube—not the stone treatment itself.
A ureteric stent sits internally between the kidney and bladder. It may be placed before or after ureteroscopy depending on drainage, access, swelling, infection risk and procedural factors.
Common stent symptomsFrequency, urgency, blood in the urine, bladder discomfort and flank pain during urination can occur.
Not every patient needs oneAfter uncomplicated ureteroscopy, routine stenting is not always necessary. The decision is individual.
Removal mattersA temporary stent needs a clear removal plan. Patients should know when and how it will be removed.
Preventing recurrence
Removing the stone does not remove the tendency to form stones.
Prevention should be tailored to stone type, recurrence risk, diet, medical history and metabolic findings rather than relying on blanket restrictions.
HydrationConsistent fluid intake is one of the most important general preventive measures, adjusted to individual medical circumstances.
Stone analysisWhen a stone is available, composition can guide counselling and further evaluation.
Dietary calciumMost calcium-stone formers should not automatically eliminate normal dietary calcium; advice should be individualized.
Metabolic evaluationRecurrent, high-risk or motivated stone formers may benefit from blood tests and one or more 24-hour urine collections.
Questions to ask before treatment
A useful stone plan should explain why this option fits your stone, anatomy and priorities.
Can this stone reasonably pass or be observed?Ask what follow-up is needed if treatment is deferred.
Why RIRS, SWL or PCNL for this particular stone?The answer should relate to size, location, density, anatomy and expected clearance.
What is the chance I will need another procedure?Staged treatment can be entirely appropriate, but it should be discussed beforehand.
Will I need a stent?Ask why a stent is expected, what symptoms it may cause and when it will be removed.
Common questions
Short answers
Does every kidney stone need surgery?
No. Some stones can be observed and some ureteric stones may pass naturally. Treatment becomes more important with obstruction, infection, repeated symptoms, stone growth, impaired renal function or a low likelihood of safe passage.
Is RIRS better than PCNL?
Neither is universally better. RIRS avoids a percutaneous tract and is useful for many renal stones. PCNL is generally more efficient for larger or complex stone burdens. The best option depends on the stone and the patient.
Will I definitely need a stent after RIRS?
No. Stent use depends on the operation, ureteric access, swelling, stone burden and surgeon judgement. Some patients benefit from a temporary stent and some do not require one.
Can stones recur after complete removal?
Yes. Stone removal treats the current stone but not necessarily the metabolic or dietary tendency that produced it. Prevention is therefore part of long-term care.
Clinical references
Patient information on this page is informed by contemporary urological guidance, including the European Association of Urology Guidelines on Urolithiasis (2026) and the American Urological Association stone-disease guidance. Guidelines support clinical decision-making but do not replace individual assessment.
Consultation
Kidney or ureteric stone opinion
If available, bring the actual CT or ultrasound images in addition to the written report, along with urine culture, kidney-function tests and details of previous stone procedures or stents.