Definition
Kidney stones are crystallized material in the urine. These stones form in the kidneys or other parts of the urinary tract. Kidney stones may be made up of a variety of minerals in the blood. The most common are calcium, oxalate, or phosphate. Others stones may contain uric acid, struvite, and/or cystine.
Kidney Stone |
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Causes
Some of the known causes of kidney stones in children include:
- Too much oxalate in the urine
- Too much calcium in the urine or blood
- Too much uric acid in the urine
- A stone can form around bacteria
- Inherited abnormality in the way the body handles cystine
- Foreign bodies in the urinary tract, such as stents or catheters
- Abnormal function of the urinary tract, such as neurogenic bladder
Risk Factors
Factors that may increase your child’s chance of developing kidney stones include:
- Dehydration —not drinking enough fluids
- Eating foods high in salt
- Eating a ketogenic diet to help control epilepsy
- Mineral content of water your child drinks (hardness or softness of the water)
- Having family members who have had kidney stones or gout
- Having kidney stones in the past
- Being overweight
- Medical conditions, such as urinary tract infections or metabolic conditions
- Geographic location—residents of the Southeast United States have an increased risk
- Limited physical activity
- Foreign material in the urinary tract, such as a catheter
Symptoms
Occasionally, kidney stones do not cause symptoms, and they leave the body in the urine. Often a kidney stone can cause symptoms such as:
- Sudden, severe pain in the side of the body or mid- or lower back during movement
- Pain in the belly or groin area
- Nausea or vomiting
- Blood in the urine
- Burning pain when urinating
- Fever
- Recurring urinary tract infections
Diagnosis
You will be asked about your child’s symptoms and medical history. A physical exam will be done.
Images of the kidneys and urinary tract may be taken with:
- Ultrasound
- KUB (kidney, ureter, bladder) x-rays
- Spiral CT scan
- Rarely, IV pyelogram (IVP)
A 24-hour urine test may also be done to look for levels of minerals in the urine including calcium , phosphorus , uric acid, oxalate, and citrate.
Treatment
Treatment depends on the size and location of the kidney stone. Treatment may include:
Water
For small kidney stones, having your child drink plenty of water will help the body pass the stone in the urine. A special cup may be provided to catch the stone when it passes so that it can be analyzed. If your child is having a hard time keeping fluids down, hospitalization may be needed to receive fluids through an IV.
Medication
Your child may be advised to take:
- Over-the-counter pain relievers
- Prescription pain relievers
- Medication to dissolve or expel the kidney stone
Surgery
Surgery may be needed if the stone is:
- Very large or growing larger
- Causing bleeding or damage to the kidney
- Causing infection
- Blocking the flow of urine
- Unable to pass on its own
Types of surgery include:
- Extracorporeal shock wave lithotripsy (ESWL)—uses shock waves to break up stones that are too large to pass
-
Ureteroscopy and stone basketing or laser lithotripsy—camera is used to locate the stone
- Stone basketing—A tiny basket is used to remove the stone.
- Laser lithotripsy—The stone is broken into smaller pieces with a laser if it is too large to remove.
- Percutaneous nephrolithotomy—uses a scope placed through a small tube in the back to remove a large stone (rare)
- Lithotomy—open surgery to remove a stone (rare)
Prevention
Once a child has had one kidney stone, more stones are likely. To help reduce your child's chance of future stones:
- Have your child drink plenty of fluids, especially water. Avoid sodas.
- Make sure your child does not eat too much food that is high in salt, such as potato chips, french fries, or processed meats.
- A calcium-rich diet can help bind oxalate before it reaches the kidney. Encourage milk and yogurt.
- If your child is overweight, work with your child’s doctor to learn the safest way for your child to lose weight.
- Encourage water during sporting activities or other active playtimes.
RESOURCES
National Institute of Diabetes and Digestive and Kidney Diseases http://www.niddk.nih.gov
Urology Care Foundation http://www.urologyhealth.org
CANADIAN RESOURCES
Health Canada https://www.canada.ca
The Kidney Foundation of Canada http://www.kidney.ca
References
Borghi L, Meschi T, et al. Dietary therapy in idiopathic nephrolithiasis. Nutr Rev. 2006;64:301-312.
Kidney stones. Cincinnati Children’s Hospital website. Available at: http://www.cincinnatichildrens.org/health/k/kidney-stones. Accessed January 29, 2021.
Kidney stones. National Kidney Foundation website. Available at: http://www.kidney.org/atoz/content/kidneystones.cfm. Accessed January 29, 2021.
Nephrolithiasis. EBSCO DynaMed website. Available at: http://www.dynamed.com/topics/dmp~AN~T114904/Nephrolithiasis . Accessed January 29, 2021.
6/23/2014 DynaMed Plus Systematic Literature Surveillance http://www.dynamed.com/topics/dmp~AN~T114904/Nephrolithiasis . Elderwy AA, Kurkar A, et al. Dissolution therapy versus shock wave lithotripsy for radiolucent renal stones in children: a prospective study. J Urol. 2014;191(5 Suppl):1491-1495.
Revision Information
- Reviewer: EBSCO Medical Review Board Chelsea Skucek, MSN, BS, RNC-NIC
- Review Date: 03/2020
- Update Date: 01/28/2021