Urology

Kidney Stones

The kidneys — two fist-sized, bean-shaped organs on either side of the spine — serve as filters, removing waste and excess fluid from the blood. That waste becomes urine. When calcium and other minerals in urine build up, stones—hard, pebble-like pieces of material — can form in the kidneys. Kidney stones are very common and occur in 1 in 11 people over their lifetime.

Kidney stones aren’t just painful. They can impact your urinary tract. Dietary factors play a major role in kidney stone formation and prevention. In some cases, kidney stones are a sign of overactive parathyroid glands in the neck, chronic kidney disease, or genetic disorders. That’s why it is crucial to have a urologic evaluation if you are diagnosed with a kidney stone. The kidney stone specialists at NewYork-Presbyterian can identify why the stones formed — based on your medical and dietary history as well as the kidney stone composition — and devise an appropriate treatment plan.

Our Approach to Kidney Stones

Unfortunately, you will probably not know you have a kidney stone when it is located in the kidney. It typically does not cause symptoms until it tries to pass and moves into the ureter, which is the narrow tube that connects the kidneys to the bladder. The stone might get lodged in the tube. The lodged stone makes it hard for the kidney to drain correctly, which can cause immense pain.

Depending on the size and location of the stone, they often pass on their own. However, in some cases medical or surgical intervention is necessary. The urologic experts at NewYork-Presbyterian/Columbia University Medical Center and NewYork-Presbyterian/Weill Cornell Medical Center work closely with nephrologists, nutritionists, and radiologists to provide comprehensive care for kidney stones. Our dedicated Kidney Stone Centers use state-of-the-art technology for the evaluation and management of kidney stones.

Diagnosing kidney stones

If your primary care provider believes you might be suffering from kidney stones, it is essential you find a board-certified urologist trained in treating diseases of the urinary tract. Our urologists and sub-specialty trained endourologists — a urologist with expertise in navigating inside the kidneys, ureter, and bladder, using endoscopic optical instruments and other tools — determine the best treatment for you based on your medical history and other factors.

To determine the best treatment, we will:

• Check temperature, heart rate, and blood pressure.
• Perform urine studies including urinalysis, urine culture, and in select cases 24-hour urine collections.
• Check blood studies to evaluate your kidney function and electrolytes, to assess for factors making you more prone to making stones, and to assess for infection.

Other diagnostic tests performed may include:

Unenhanced/Non-contrast Computed Tomography (CT) scan. This is the most accurate imaging test for kidney stone disease but involves ionizing radiation. It gives very detailed information about the stone features such as size and location, which helps guide the physician with treatment options. We also attempt to use low-dose CT scans (very low radiation CT scan imaging) whenever possible, to limit your risk of radiation exposure.

Ultrasound. Kidney and bladder ultrasound is useful in the evaluation of potential blockage during an acute pain episode as a stone tries to pass, and can quite often identify the stone location and approximate size to aid us in the decision process as to the optimal treatment option. It is also used to monitor patients long-term for recurrent kidney stones. Although it is less accurate than CT, it does not involve any radiation making it very safe.

Kidney, ureter, and bladder (KUB) X-ray. Like ultrasound, KUB can be used during an acute pain episode or kidney stone follow-up but involves a small amount of ionizing radiation. If the stone is large enough and radiopaque or visible on X-ray, it can commonly be seen on KUB. However, it is also less accurate than CT.

Metabolic evaluation. All stone patients undergo a basic metabolic evaluation to determine possible causes of their kidney stone. This includes baseline serum or blood tests as well as urine tests (urinalysis, urine culture, and stone analysis if available). High-risk patients such as those with recurrent stones, solitary kidneys, and certain medical conditions like obesity, diabetes, gout, bowel disorders, and chronic kidney disease undergo more comprehensive metabolic evaluation. This includes 24-hour urine collection(s) to determine urinary parameters that may be causing their stones. However, metabolic evaluation is typically not done during the acute management of a stone. Rather, it is done approximately one to two months later to guide dietary changes and possibly prescribe medications for future stone prevention.

Therapeutic Approaches

Kidney stone treatment options can range from dietary intervention to surgery depending on the size, location, and composition of the kidney stones, as well as the patient’s symptoms and medical conditions. At NewYork-Presbyterian, our comprehensive care team of nurses, urologists, nephrologists, anesthesiologists, radiologists, nutritionists, and researchers, work with patients and their referring physician to find the optimal treatment plan.

As one of the leading urologic treatment programs in the country our patients have access to the most advanced surgical and medical therapies for the treatment of kidney stones.

Medical therapies to facilitate stone passage

Most kidney stones do not require surgery. For patients with ureteral stones less than 10-millimeters, we can typically attempt a trial of stone passage. During this time, patients try to pass the stone naturally. We carefully monitor their pain level, kidney function, and ensure there is no evidence of infection. Key components of a trial of passage include:

Pain management. Pain relievers such as ibuprofen (Advil, Motrin), acetaminophen (Tylenol), or naproxen sodium (Aleve) are recommended to relieve the pain from stone passage. In some cases, stronger prescription pain medications may be prescribed.

Medical expulsive therapy. Drugs known as alpha-blockers work by relaxing the muscles in the ureter. One common example is tamsulosin (Flomax), which can be used off-label to help aid in the stone passage. These are given to facilitate passage of kidney stones that have moved into the ureter. Studies have shown alpha-blockers not only increase the chance of stone passage but can also make the stone pass faster and with less pain.

Medical therapy to prevent stone growth and formation

In some cases, particularly in patients who are recurrent stone formers or have complex stones, a full metabolic evaluation is warranted to determine individual risk factors for stone formation. This usually entails specialized blood, and urine tests and an evaluation of the consistency of any prior stones passed or removed. Based on this evaluation we can work with our nutritionists to recommend an individualized diet plan or potentially start medications to prevent stone growth or reformation. We also may refer you to one of our nephrology colleagues who also specialize in kidney stone prevention to aid in your prevention of recurrent stones.

Surgical therapies

Kidney stones that do not pass on their own or with medication will need to be treated surgically. At NewYork-Presbyterian, we perform a wide range of minimally invasive kidney stone removal procedures. These are typically done under general or regional anesthesia. By performing minimally invasive surgery, patients can recover faster, have smaller incisions or often no incisions, spend less time in the hospital, and reportedly experience less post-operative pain.

Ureteroscopy with Laser Lithotripsy. During this incision-free surgery, our surgeons pass a thin fiber-optic telescope equipped with a camera called a ureteroscope through your urethra and bladder and into your ureter. It is then used to visualize and treat the stone directly. If the stone is too large to remove safely, it is first broken down into smaller pieces with a laser fiber. Surgical tools called baskets are then inserted to retrieve the stone or stone fragments. The stones removed can be sent for analysis to determine their composition. At the conclusion of the procedure, a stent is commonly placed in the ureter to relieve swelling, gently dilate the ureter, help pass stone fragments (typically after the stent is removed), and promote healing. This stent is only temporary and must be removed in a timely fashion to prevent complications. Ureteroscopic laser lithotripsy is usually an outpatient procedure and is now the most common procedure worldwide for kidney stones.

Shockwave lithotripsy (SWL). This non-invasive outpatient procedure uses sound energy to create shockwaves to fragment the stones into smaller pieces. The patient must then pass these pieces on their own after the procedure. SWL can cause blood in the urine, bruising on the back or abdomen, bleeding around the kidney and other adjacent organs, and discomfort as the stone fragments pass through the urinary tract. Depending on the stone size, stone-related symptoms and degree of kidney obstruction, a stent may be placed in the ureter as well.

Percutaneous Nephrostolithotomy (PCNL). Patients with large greater than 2 cm, multiple or complex kidney stones benefit from an inpatient procedure. A small incision is made in the back, and a protective sheath is inserted into the kidney. A video scope called a nephroscope is then introduced through the back to locate, fragment, and remove the stone and stone fragments. A stent or nephrostomy tube is often placed at the end of the procedure to help the kidney drain and heal.

Next Generation Therapeutic Care through Research

Through the research conducted at Columbia University College of Physicians and Surgeons and the Weill Cornell Medical College, the physicians and staff at NewYork-Presbyterian can identify causes of disease, refine surgical tools, and advance the field of urology. That means our patients have access to the treatments of tomorrow, today. To learn how you can help us continue to improve our understanding of kidney stones, visit our clinical trials page.

Appointments & Referrals

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Refer a patient

At NewYork-Presbyterian, we treat a diverse patient population with conditions ranging from the most common to the rarest and most complex. Clinicians in private practice or at other hospitals are welcome to refer their patient to NewYork-Presbyterian. Please call 212-305-0114 or 646-962-9600 to arrange a referral.