
Key Takeaways
In this article, you’ll clearly understand:
- When do kidney stones require surgical treatment, and when don’t they
- What size of a kidney stone usually requires surgery
- How doctors decide surgery based on stone size, symptoms, and blockage
- Whether common stone sizes like 5mm, 6mm, or 15mm need surgery
- Why some kidney stones must be removed surgically
- What happens if a kidney stone is left untreated
- Whether kidney stone surgery is a major operation and the risks involved
Introduction
When do kidney stones require surgical treatment is a common concern for people diagnosed with kidney stones. While many stones pass naturally with fluids, medication, and time, some cases require surgical intervention to prevent severe pain, infection, or long-term kidney damage.
This article explains when kidney stones need surgery, how doctors make decisions based on stone size, symptoms, and complications, and what can happen if treatment is delayed. By the end, you’ll have a clear understanding of whether surgery may be required in your case and when it is important to seek specialist care.
Understanding when kidney stones require surgical treatment depends largely on stone size, symptoms, and associated complications.
What Size Kidney Stones Need Surgery
The size of a kidney stone plays an important role in deciding treatment. Smaller stones often pass naturally, while larger stones are more likely to get stuck in the urinary tract and cause complications.
However, size alone is not the only deciding factor. Doctors also consider pain severity, infection, urine blockage, kidney function, and how long the stone has been present. When stones are unlikely to pass on their own or cause complications, kidney stone treatment through medical or surgical methods may be required.
These factors together help doctors determine when do kidney stones require surgical treatment rather than continued observation or medical management.
How Much mm Kidney Stone Needs Surgery
Stones < 5 mm
Most kidney stones under 5 mm pass naturally through urine. Surgery is usually not required unless the stone causes severe pain, infection, or urinary obstruction.
Clinical data show that ureteral stones smaller than 5 mm have a greater than 75% chance of spontaneous passage, and passage rates may reach up to 95% with time and observation, depending on location and patient factors.
Stones Between 5–7 mm
These stones fall into a borderline category. Some may pass on their own, but surgery may be considered if pain persists, urine flow is blocked, or the stone does not move for several weeks.
Studies demonstrate spontaneous passage rates of around 60% for stones measuring 5–7 mm, with decreasing likelihood as stone size increases.
Stones Larger Than 7–10 mm
Stones in this range have a much lower chance of passing naturally and are more likely to require medical or surgical intervention.
Meta-analysis data from the AUA/EAU guideline panel indicate that only approximately 47% of stones larger than 5 mm and up to 10 mm pass spontaneously; therefore, observation is not recommended in patients with persistent pain, urinary obstruction, infection, solitary kidney, or renal impairment.
Stones Around 15 mm or Larger
Large kidney stones rarely pass without intervention. Surgery is usually advised to prevent kidney damage, recurrent infections, or worsening symptoms.
According to the American Urological Association Surgical Management Guideline, clinicians should not offer shockwave lithotripsy as first-line therapy for kidney stones larger than 1 cm in certain locations, and for stones larger than 2 cm, percutaneous nephrolithotomy (PCNL) is recommended as first-line therapy.
(AUA Surgical Management of Kidney and Ureteral Stones, 2026 – Statements 18 & 22)
Do All Kidney Stones Need Surgery
No. Most kidney stones do not require surgery. Many patients can be managed with hydration, medications, and monitoring, especially when stones are small and not causing complications.
In such cases, lifestyle changes and preventive measures play an important role in reducing recurrence. Learning how to prevent kidney stones can help lower the chances of future stone formation and avoid the need for surgical treatment.
Which Kidney Stones Require Surgery
Kidney stones are more likely to require surgical treatment when doctors assess when do kidney stones require surgical treatment based on symptoms, obstruction, and kidney function:
- Block the flow of urine
- Cause persistent or severe pain
- Are associated with fever or infection
- Remain in the urinary tract for a long time
- Affect kidney function
In these cases, timely kidney stone treatment helps prevent serious complications.
Why Do You Need Surgery for Kidney Stones
Understanding when do kidney stones require surgical treatment helps explain why surgical intervention is sometimes safer than delaying care:
- Relieve ongoing pain
- Prevent kidney damage
- Avoid serious infections
- Remove stones that cannot pass naturally
- Reduce the risk of long-term complications
Clinical outcome data show that for stones larger than 15 mm, stone-clearance rates are significantly higher with PCNL compared to ureteroscopy, supporting surgical intervention for large stones.
How Often Do Kidney Stones Require Surgery
Only a small percentage of kidney stone cases require surgery. Most stones pass naturally. Surgery is more common in people with:
- Large stones
- Recurrent kidney stones
- Structural urinary tract problems
Does 5mm Kidney Stone Need Surgery
A 5mm kidney stone usually does not need surgery. Many pass naturally. Surgery may be advised if the stone causes severe pain, blockage, or does not pass after a reasonable period.
Does 6mm Kidney Stone Need Surgery
A 6mm kidney stone has a lower chance of passing naturally compared to smaller stones. Doctors may initially monitor it, but surgery may be recommended if symptoms persist or complications develop.
Does 15mm Kidney Stone Need Surgery
In most cases, yes. A 15mm kidney stone is unlikely to pass on its own and often requires surgical removal to prevent kidney damage or infection. Early kidney stone treatment is usually advised.
Conclusion
Understanding when kidney stones require surgical treatment is essential, as kidney stones do not always require surgery but need timely evaluation to prevent complications. Stone size, symptoms, and associated complications determine whether surgical treatment is necessary. Early medical assessment helps prevent long-term kidney damage and serious infections.
If you are experiencing persistent symptoms or complications and want expert evaluation for kidney stone treatment, you can contact us to schedule a consultation and receive personalized medical guidance.
FAQs –About Kidney Stone Surgery
Which size of kidney stone needs surgery?
Stones larger than 7–10 mm are less likely to pass naturally and may require medical or surgical treatment, depending on symptoms and complications.
Do all kidney stones require surgery?
No. Many kidney stones pass on their own without surgery.
How do I know if I need surgery for a kidney stone?
Surgery may be needed if the stone causes severe pain, infection, blockage, or does not pass over time.
Can kidney stones go away without surgery?
Yes. Smaller stones often pass naturally with fluids and medication.
Is removing a kidney stone a big operation?
Most kidney stone procedures today are minimally invasive and not considered major surgery.
What happens if a kidney stone is left untreated?
Kidney stones that block the urinary tract can cause pain, infection, or kidney damage and may eventually require medical or surgical treatment.
What happens if a kidney stone stays in too long?
Long-standing stones can block urine flow and gradually impair kidney function if not treated.
Related Links
- AUA / EAU Guideline Panel – Spontaneous Passage of Ureteral Stones
https://pmc.ncbi.nlm.nih.gov/articles/PMC3897056/ - Renal & Urology News – PCNL vs URS Outcomes (JAMA Network Open)
https://www.renalandurologynews.com/news/urs-pcnl-kidney-stone-removal-older-children-treatment-risk/ - American Urological Association – Surgical Management of Kidney and Ureteral Stones (2026)
Statements 18 & 22