Kidney Stones | Frequently Asked Questions

What do the kidneys do?

The kidneys are the body's filtering system. They help control water levels and eliminate excess minerals and waste products by producing urine.

What are kidney stones?

Kidney stones are solid deposits of minerals and salts that build up in the urine collecting areas within the kidneys. They may start as microscopic particles, but over time, they grown large enough to see.

Why are kidney stones a problem?

They can get lodged in the urinary tract and obstruct the flow of urine. Although most stones won’t cause long-term damage to your child, passing kidney stones can be extremely painful. Obstruction of the kidney can be dangerous because it can lead to infection or injury to the kidney, so it is important to get the problem diagnosed early.

What is the long-term outlook for my child?

It depends on what is causing your child to develop the stones. Some children form a single stone and never have another stone again. Others have multiple episodes of stones. Children with underlying genetic, anatomic or biochemical causes for stone formation are more likely to form multiple stones, and it is important that these conditions be identified and treated.

Some underlying medical conditions that lead to stones are lifelong and must be managed as such.

How common are kidney stones? 

Stones are not common in children, but they're getting more so.

Some children who form urinary stones have an underlying abnormality of the urinary tract. These can include obstructions of the kidney and ureter (the tube that connects the kidney with the bladder) or diseases such as spina bifida.

However, most children with stones have normal urinary tract anatomy.

We believe that the increase in kidney stones may reflect lifestyle factors such as childhood obesity, diets with excess salt and not drinking enough water. There are also genetic factors that play a role and we are still learning about these. Several studies are taking place at Boston Children's Hospital to understand what genes contribute to kidney stones in children.

At what age do children typically form stones?

Stones can form in children of any age, but we generally see school-aged children and older. We also see premature babies whose course in the NICU let to risk of stones or whose medications throw off the balance of minerals in their urine and lead to kidney stone formation. Rarely, these babies may have more severe inheritable reasons for kidney stones.

Are kidney stones more common in boys or girls?

Stones can form in both boys and girls. Although stones in adults are more common in men than in women, the difference is not nearly as great in children.

Do environmental conditions affect stone formation?

Yes. We see more cases in the summer and fall when children tend to be more active, sweat more and are more prone to dehydration.

The highest concentration of Americans with kidney stones come from what we refer to as the "Stone Belt" in the southeastern states. This is probably due to the warm weather in those states, which can cause chronic dehydration, but there are probably other environmental and genetic factors that cause some areas to see more stones than others.

How long does the appointment take?

Your first appointment usually takes two hours. If we need to perform diagnostic imaging, it can add some time to your visit.

After we complete all necessary tests, our experts meet to review and discuss what they have learned about your child's condition. Then we will meet with you and your family to discuss the results and outline the best treatment options.