Kidney Stones

Kidney stones, medically known as nephrolithiasis, are hard deposits in the kidneys that are made of salt and minerals. In some cases, kidney stones can be passed naturally from the body, although the symptoms can be quite painful. Larger kidney stones can lead to kidney disease and may require medical treatment, including surgery.

As part of an academic medical center connected to ongoing research, The University of Kansas Health System learns of the latest medical advances while they’re developing. Because of this, our patients are often among the first to benefit from new kidney stone treatment options through access to clinical trials.

Every person has some amount of salt, minerals and other crystal-forming substances in their urine. Kidney stones form when there is not enough fluid in your urine to dilute those substances, and they clump together.

After kidney stones form, they can either pass from the body through the urinary tract during urination or they can stay in the kidney. Sometimes, kidney stones can pass in the urine stream without much discomfort. However, larger kidney stones can be quite painful to pass. Kidney stones that cause irritation or blockage can cause severe pain and lead to infection.

The 4 main types of kidney stones are named for their primary chemical components:

• Calcium-based stones: These are the most common type of kidney stones and are primarily composed of calcium oxalate and calcium phosphate. They are associated with high levels of calcium and sodium in the urine. High levels of oxalate is also a risk factor for formation of these stones.
• Struvite stones: Also called infection stones, struvite stones are typically caused by urinary tract infections (UTIs). They can grow rapidly and become quite large.
• Uric acid stones: Uric acid stones form when there is an excess of uric acid in the urine. This can be a result of a diet high in purines or certain medical conditions.
• Cystine stones: These stones are rare and form in people with a hereditary condition called cystinuria. Cystine, an amino acid, leaks into the urine and forms crystals that can accumulate into stones.

Kidney stones can vary widely in size, and the symptoms vary accordingly. Very small kidney stones may have no symptoms at all. Kidney stone pain can also change in intensity and location as the stone moves down the urinary tract.

Possible kidney stone symptoms can include:

• Severe pain: This is often the most noticeable symptom. The pain can come in waves and may radiate from the back, down the side, and into the groin area. It’s often described as one of the most painful experiences.
• Hematuria: Blood in the urine is a common sign, which can make the urine appear pink, red, or brown.
• Frequent urination: Individuals may feel the need to urinate more frequently, and the urge can be intense.
• Painful urination: Discomfort or a burning sensation during urination can occur.
• Cloudy or foul-smelling urine: The presence of kidney stones can affect the appearance and odor of urine.
• Nausea and vomiting: Some people may experience nausea and vomiting, often as a result of the severe pain.

There is no single cause for kidney stones, and anyone can be at risk for developing kidney stones. Some risk factors could increase your chances of getting kidney stones:

• Dehydration: Insufficient fluid intake can lead to concentrated urine, increasing the risk of stone formation.
• Diet: A diet high in sodium and animal protein combined with low fluid intake can contribute to stone formation. Certain foods rich in oxalate, such as spinach, beets and nuts, may also increase the risk.
• Family history: A family history of kidney stones can predispose an individual to develop them.
• Medical conditions: Some medical conditions, like gout, obesity and certain metabolic disorders, can increase the likelihood of forming kidney stones.
• Urinary tract infections (UTIs): Infections that lead to the formation of struvite stones are another cause.
• Medications: Certain medications, such as diuretics, antacids and some medications for migraines can increase the risk of stone formation.
• Surgeries: Some types of surgery, such as gastric bypass surgery, can increase the risk of developing kidney stones.

There are several tests your doctor may suggest to identify the presence of a kidney stone:

• Blood tests to check your kidney health as well as measuring the calcium content and uric acid levels in your blood
• Imaging tests such as a CT scan or ultrasound
• Urine analysis to check the amounts of stone-forming minerals that are present in your urine

If you’ve already passed a kidney stone, your doctor may analyze the mineral composition of the stone to determine the cause for its growth. From there, you can work together to develop a preventive treatment plan to limit the formation of additional kidney stones.

Choosing the best treatment for your kidney stones depends on the size of the stones. Common treatment approaches for small stones include:

• Watchful waiting: Small kidney stones that are not causing significant symptoms may pass on their own with pain management and increased fluid intake. Your doctor may recommend monitoring the stone’s progress.
• Pain management: Severe pain is often treated with pain relievers, such as ibuprofen or stronger prescription medications.
• Hydration: Drinking plenty of water is crucial to help flush out kidney stones and prevent their formation. Your doctor may advise you to increase your fluid intake significantly.
• Medical expulsion therapy: This involves taking medications that can help relax the muscles in the ureter, making it easier for the stone to pass.

At The University of Kansas Health System, we offer today's leading-edge treatments for large kidney stones.

• As a part of an academic medical center, we offer the latest treatment options, including access to groundbreaking clinical trials. These therapies often reduce recovery time and improve outcomes.
• Our experts have significant experience performing the latest kidney stone procedures with great success. Their expertise allows most people to be treated using a minimally invasive approach – avoiding incisions.
• Working closely with our interventional radiologists, we offer the latest in imaging techniques for kidney stone diagnosis and treatment, resulting in excellent success rates.