Dr. Pavel Gavrilov

While they stay still in the kidney, many stones cause no symptoms. When they move into the ureter they can cause renal colic:

• Very intense pain in the lower back or side, which may spread to the groin or genitals
• Nausea and vomiting
• Blood in the urine
• Frequent urge to urinate or burning

• If the pain comes with fever or chills (there may be an infection with blockage, which is an emergency)
• If you cannot pass urine
• If you have only one kidney
• If the pain does not ease with painkillers

• Urine and blood tests
• Ultrasound
• Non-contrast CT scan: the most accurate test to see the size and location of the stone

The choice depends on the size, location and composition of the stone, and on whether it causes symptoms or complications.

Spontaneous passage

Small stones usually pass on their own with painkillers and, sometimes, medication that helps them pass.

Extracorporeal shock wave lithotripsy (ESWL)

Breaks the stone from outside the body, with no incisions. The fragments are then passed in the urine.

Flexible ureteroscopy with laser

The stone is reached through the urethra with a very thin endoscope and broken up with a laser. There are no skin incisions.

Percutaneous nephrolithotomy (PCNL)

For large kidney stones: access through a small incision in the back.

• Drink enough water to keep your urine pale (generally aiming for about 2–2.5 litres of urine a day, more in summer)
• Reduce salt and animal protein
• Avoid too many sugary soft drinks
• Do not cut calcium from your diet without medical advice: a normal calcium intake helps prevent some types of stones
• If stones recur, analyse their composition and carry out a metabolic study to personalise prevention

Stones often recur, which is why prevention is so important. With proper assessment and changes in diet and hydration, the risk goes down.

No. Many small stones pass on their own. Treatment is needed when the stone is large, does not pass, or causes repeated pain, infections or blockage.

Patients usually go home the same day or the next day. Sometimes an internal stent (double-J) is left in place for a few days or weeks and then easily removed in the clinic.

The usual advice is to drink enough to pass about 2 to 2.5 litres of urine a day: in practice, your urine should be pale. You need more in summer or if you exercise. If you have a heart or kidney condition, check the amount first.

Salt, too much animal protein and sugary soft drinks. Do not cut calcium out of your diet on your own. Analysing the stone’s composition allows specific advice for your case.