Kidney stones and urinary tract infections (UTIs) are both incredibly common urological conditions – but can one actually cause the other? The short answer is yes, and understanding the connection between them is important for protecting your long-term urinary health.
How kidney stones and UTIs are linked
Kidney stones are hard mineral deposits that form in the kidneys and can travel through the urinary tract. While they are painful enough on their own, they can also create the ideal conditions for a UTI to develop.
Here’s how:
- Obstruction: A stone lodged in the ureter or bladder can block the normal flow of urine. When urine stagnates, bacteria have an opportunity to multiply, significantly increasing the risk of infection.
- Tissue damage: As a stone moves through the urinary tract, its rough, jagged edges can scratch and irritate the lining of the ureter and bladder. This damage makes it easier for bacteria to take hold.
- Incomplete bladder emptying: Stones that partially obstruct the lower urinary tract can prevent the bladder from emptying fully. Residual urine left behind is a breeding ground for bacteria.
It is also worth noting that the relationship can work in the opposite direction. Certain bacteria – particularly Proteus mirabilis – produce enzymes that make urine more alkaline, which directly encourages the formation of a specific type of stone called a struvite stone. So while a kidney stone can trigger a UTI, a recurrent UTI can, in turn, lead to more stones.
Recognising when you have both
Overlapping symptoms can make it difficult to tell whether you are dealing with a kidney stone, a UTI, or both at the same time. Knowing what to look out for is key.
Symptoms of a kidney stone
- Severe, cramping pain in the lower back or side (renal colic)
- Pain that radiates to the groin or, in men, the testicles
- Blood in the urine, which may appear pink, red, or brown
- Nausea and vomiting
Symptoms of a UTI
- A burning or stinging sensation when urinating
- Needing to urinate more frequently than usual
- Cloudy or foul-smelling urine
- A persistent feeling of pressure in the lower abdomen
When both are present
If you have a kidney stone alongside an infection, you may experience a combination of the above, plus fever and chills. This is a serious warning sign. A kidney infection caused by an obstructed, infected stone – known as an obstructive pyelonephritis – is a medical emergency requiring urgent treatment. If you develop a high temperature alongside kidney or flank pain, you should seek medical attention immediately.
Who is most at risk?
Certain groups are more likely to experience kidney stones and UTIs concurrently:
- People with recurrent UTIs – particularly those caused by urea-splitting bacteria – have a higher risk of struvite stone formation
- Those with structural urinary abnormalities, where incomplete drainage of the urinary tract is more likely
- People with a history of kidney stones, as around 50% will experience a recurrence within five to ten years
- Women, who are statistically more prone to UTIs due to a shorter urethra, though men with kidney stones are not immune to infection
How is it treated?
Treating a kidney stone-related UTI requires addressing both problems. A urologist will typically:
- Diagnose the extent of the problem using urine tests, blood tests, and imaging, such as a CT scan, to identify the stone’s size and location.
- Prescribe antibiotics to clear the infection – though it is important to note that antibiotics alone will not resolve the stone.
- Treat or remove the stone to eliminate the underlying cause.
For smaller stones, conservative management with pain relief and medication to relax the ureter may be sufficient, allowing the stone to pass naturally. For larger or obstructing stones, treatment options include:
- Ureteroscopy and laser stone fragmentation
- Extracorporeal shock wave lithotripsy (ESWL)
- Percutaneous nephrolithotomy (PCNL) (for more complex cases).
In emergency situations with a blocked, infected kidney, a temporary drainage procedure (such as a JJ stent or nephrostomy) may be needed to relieve pressure and allow safe treatment of the infection before definitive stone removal.
Reducing your risk
Preventing future stones – and the infections that can come with them – involves some straightforward but effective lifestyle measures:
- Stay well hydrated: Aiming for two to three litres of water daily helps dilute urine and reduces the concentration of stone-forming minerals.
- Watch your diet: Limiting salt, excessive animal protein, and foods high in oxalates (such as spinach, nuts, and chocolate) can lower your risk.
- Treat UTIs promptly: Getting infections treated quickly reduces the chance of bacteria contributing to stone formation.
- Attend follow-up appointments: If you have had a stone before, regular monitoring with your urologist is important to catch any recurrence early.
When to see a specialist
If you are experiencing recurrent UTIs, persistent kidney pain, blood in your urine, or have previously had kidney stones, it is worth seeking specialist advice. These symptoms should never be dismissed, as untreated stones and associated infections can cause lasting damage to kidney function over time.
At Urocare London, Consultant Urologist Mr Maneesh Ghei offers expert assessment and a full range of treatments for kidney stones and related urinary conditions. Getting an accurate diagnosis early makes all the difference – both in terms of treatment outcomes and peace of mind.
