Kidney Stones in Children

Urolithiasis or nephrolithiasis, which is commonly known as kidney stones occur rarely in children. Kidney stones cause excruciating pain in children and parents tend to panic and become helpless.

What are Kidney Stones?

Collection of some materials, such as minerals and acid salts form small stone-like structures within the urinary tract. These stones block the free flow of urine causing pain. Although kidney stones are rare in children, the number of cases where children develop stones is growing. Generally, children recover without future complications. However, if kidney stones are not treated on time, it can lead to kidney problems.

How do Kidney Stones Develop?

The urinary tract comprises of two kidneys, ureters, a bladder and the urethra. The urine contains substances such as calcium, cysteine, oxalate and uric acid. When the level of these substances is higher, they crystallise. If these crystals are small, they move within the urinary tract and pass out of the body through urine. If they are not flushed out, they rest on the kidney and increase in size. As the size increases, it causes pain and sometimes blocks urine flow. Stones that are less than 0.2 inches can pass through easily.

How Common are Kidney Stones in Kids?

The chances of kidney stones developing in adults are higher when compared to children. Typically, most of the children with kidney stones have an existing medical condition, which increases the chances of them developing kidney stones.

Types of Kidney Stones

There are four types of kidney stones, which are:

1. Calcium Stones

These stones are the most common type among the four. There are two types of calcium stones:

• Calcium oxalate – a combination of calcium and oxalate
• Calcium phosphate – a combination of calcium and phosphate

2. Cystine Stones

These stones are rare and occur due to genetic disorders. Cystine is a chemical that the body makes naturally. In people with genetic disorders, cystine leaks into the urine through the kidneys.

3. Uric Acid Stones

If the urine is acidic, there are chances of developing uric acid stones. These stones can be formed by the acid itself or by combining itself with calcium.

4. Struvite Stones

These stones develop in people who have recurrent urinary tract infections. In some Urinary Tract Infections (UTI), bacteria make ammonia. The ammonia in urine can cause stone formation. These stones are made up of phosphate, ammonium and magnesium.

What Causes Kidney Stones in Child?

Following are some of the causes of developing kidney stones:

• Higher mineral content in the urine.
• Highly concentrated urine, wherein the water content is low, and the mineral content is high.
• Less water intake or dehydration.
• Some stones develop due to genetic disorders. Although these cases are rare, inborn metabolic issues lead to stone formation. The body makes stones due to certain genetic conditions.
• A family history of kidney stones.
• Defects in the urinary tract or persistent UTI.
• Obesity and reduced activity.
• A diet that has high sodium, protein, or both.

In some cases, the causes for developing kidney stones are unknown.

Kidney Stone Signs and Symptoms in Kids

Following are some of the common symptoms

• Abdominal or back pain
• Hematuria or blood in the urine
• Frequent urination
• Nausea or vomiting
• The urgency to urinate
• Recurrent UTI or urinary infections that exist for longer periods
• Fever

How is Kidney Stone Diagnosed in a Child?

To ascertain the presence of kidney stones and treat children, physicians recommend a comprehensive diagnosis. Typically, a complete diagnosis includes:

• Understanding the child’s medical history
• Physically examining the child
• Performing lab and imaging tests

Medical History

The first step in diagnosing involves understanding your child’s medical history. This helps the doctor in understanding whether there is a family history of kidney stones or any other genetic disorder that can be the cause. Previous conditions and treatments give doctors a clear idea about the child’s health conditions.

Physical Examination

Typically, a paediatric urologist and a paediatric nephrologist physically examine your child and also discuss the child’s health and dietary intake, specifically fluids. If you have managed to collect a stone that was passed out while urinating, the doctor examines it and sends it out to the lab for performing further tests.

Lab and Imaging Tests

Doctors recommend a couple of lab tests to diagnose various aspects about the kidney stones. Following are some of the tests:

• Urine and Blood Tests – Urine analysis is important to determine the factors that lead to stone formation. For example, high calcium levels in the urine can cause stones. Blood tests are used to identify other risk factors that can be the cause or might affect the child.
• Genetic Tests – As some genetic disorders can cause kidney stones, genetic tests are performed to evaluate and determine the risk factors.
• Scanning Tests – Doctors examine the urinary tract for kidney stones by performing an ultrasound scan. If the ultrasound results are inadequate, a Computed Tomographic (CT) scan is performed. Sometimes, an X-ray is also performed.
• Imaging Tests – Imaging tests are used to determine the precise size and the exact location of the stone, which is useful during treatment.
• Other Tests – Determining the chemical composition of the stone, if it has been collected while urinating can help in identifying the stone type. It also helps in analysing the causes of the stone formation.

Risks

Following are some of the factors that increase the risk of developing kidney stones in children:

• If the child has a past history of kidney stones, there are chances of it reoccurring.
• The fluid intake by a child directly impacts the urine formation. Drinking less water or other fluids leads to less urine formation, which increases the risk of developing stones.
• Diets that are low in carbohydrates are known as ketogenic diets. Following this diet increases the risk of kidney stone formation.
• Children who have cystic fibrosis are at a greater risk of developing stones.
• Abnormalities in the kidneys, ureters, or bladder since birth increase the risk of developing kidney stones.
• Use of some medicines contributes to stone formation in the urine. For example,
  • furosemide (Lasix)
  • acetazolamide (Diamox)
  • allopurinol (Aloprim, Zyloprim)
• Rare genetic disorders that are inherited from parents or from the family line can increase a child’s risk of developing kidney stones.
• Complications of kidney stones in kids can occur due to increased intestinal oxalate absorption (Inflammatory bowel disease), which impacts the oxalate level in the urine.

Treatment

Some of the following treatments are used to eliminate the stones:

• Extracorporeal Shock Wave Lithotripsy (ESWL) is one of the common treatment methods used in children. A lithotripter is used to send acoustic shock waves through the skin to crush the stones. These stones can move easily through the urinary tract and pass out of the body. ESWL does not need incisions but is performed under anaesthesia.

• Ureteral Stent is required if there is a blockage in the ureter or the ureter is narrowing. The ureter is a tube that transports urine to the bladder from the kidney. A stent is a soft tube that is placed in the ureter to help urine flow. A child with a stent can move around but should avoid strenuous activities.

• Percutaneous Nephrolithotripsy(PCNL) is preferred for treating large kidney stones. In this method, a tube passes through an incision in the child’s back. The tube is inserted into the kidney, and the doctor uses nephroscope to locate and remove the stones.

• Nephrostomy Tube Procedure for Kidney Stones uses a small tube to drain the urine. If the kidney stone is blocking urine drainage, this tube is used so that damage to the kidney and infections can be curbed. In this procedure, an external bag is used to drain the urine.

• Ureteroscopy uses a small scope, which is sent through the urethra into the urinary bladder, then into the ureters and kidneys. Cameras fixed to the scope help doctors to locate and remove stones using various instruments.

Home Remedies

Following are some home remedies:

• Increasing the fluid intake helps in increasing the urine formation and decreasing the quantities of mineral components that form stones.
• Basil is known to help in stabilizing uric acid levels. This can prevent kidney stone formation. It also has acetic acid, which helps in dissolving some stones.
• Pomegranate’s antioxidant properties might reduce the chances of developing stones.

How to Prevent Your Child from Developing Kidney Stones?

After treating the kidney stones, you might wonder, “Can children get kidney stones, again?” Children with a history of kidney stones have a chance of developing it again. However, the precautions can be taken to minimize the chances:

• Drinking water is the best solution.
• Additionally, continuous monitoring to determine the presence of new stones is helpful.

Kidneys are important organs and damage to it can be harmful. Although kidney stones are uncommon in kids, it is always better to take precautions, wherever required.