Q: My daughter is 4.5 years old. She was diagnosed with a 9 mm stone in her left kidney earlier this year. Since then I have taken her for sonography 4 times. Every time it gives a different size of the stone. First time it was 9 mm; second time it was 7 mm; Third time - 7 mm + 3 mm and the last time it was 9 mm. Recently we did a drip system at a children's hospital. Doctors say that every time, her body creates a new stone, so even if we opt for lithotripsy, it will be useless. What should we do?

A:Slight variation in size of stone on ultrasound is common and does not affect the management. It is important to know whether the stone is causing an obstruction to urine flow, in which case treatment is required earlier. Lithotripsy at a centre that can handle children of this age can be a good option if treatment is required.