What're treatment options for kidney stones?
Treatments of kidney stones include dietary modifications (including the advice to drink plenty of water), medications, and use of a lithotriptor. Surgery is rarely used to remove kidney stones; instead pain management is used while waiting for the stone to pass on its own. However, in severe cases, extracorporeal shock wave lithotripsy, retrograde intrarenal surgery, percutaneous nephrolithotripsy, or open surgery may be necessary. This is especially so if the stone is stuck, causing obstruction and infection of the urinary tract.
Surgery is usually needed if the stone is too large to pass on its own, if there are indications that it is growing, or if it is blocking the urine flow and causing urinary tract infection or damaging the kidney. Until recently, the procedure to remove a stone was a very painful, major surgery that required a four- to six-week recovery period. Today, treatments for stones are much less invasive and major surgery is performed in less than 2% of patients.
Extracorporeal shock wave lithotripsy (ESWL). In general, ESWL is the first choice for small stones (less than one centimeter) in the upper ureter. Extracorporeal shock wave lithotripsy (ESWL) is the most frequently used procedure for most simple stones located in the kidney or upper urinary tract, including struvite stones. It is not used for cystine stones. ESWL is generally not successful for stones larger than three centimeters in diameter (which is slightly over an inch). Most ESWL procedures use some anesthesia, although they are often done on an outpatient basis. The patient is positioned in a water bath. The procedure uses ultrasound to generate shock waves that travel through the skin and body tissues until they hit the dense stones. (X-rays or ultrasound are used to help the surgeon pinpoint the stone during treatment.) The stones are crushed into tiny sand-like pieces that usually pass easily through the urinary tract. The shattered stone fragments may cause discomfort as they pass through the urinary tract. In such cases, the doctor may insert a small tube called a stent through the bladder into the ureter to help the fragments pass. This practice, however, has not proved to speed up passage of the stones in most cases and is not used routinely.
Percutaneous nephrolithotomy (PNL). PNL can be used for very large stones in the upper tract, when ESWL fails, for kidney transplant patients, or when there are structural abnormalities in the kidney or surrounding area. It is the preferred procedure for drug-resistant cystine stones, which are usually resistant to shock wave therapy. For small staghorn calculi in normal or near normal kidneys, either ESWL or PNL is usually effective. For complicated conditions involving staghorn calculi, however, experts usually recommend PNL followed by ESWL (called a sandwich procedure) or a repeat PNL procedure. Percutaneous nephrolithotomy may be used when ESWL is not available or effective (eg, if the stone is very large, in an inaccessible location, or is a cystine stone). It is more effective for patients with severe obesity. It appears to be safe for the very elderly and the very young. Long-term effects are unknown. It is also preferred over ESWL for stones that have remained in the ureter for more than four weeks. The surgeon makes a tiny incision in the back and creates a tunnel directly into the kidney. The surgeon then inserts an instrument called a nephroscope through the tunnel. The stone is located and removed. (An advantage of percutaneous nephrolithotomy over ESWL is that the surgeon is able to remove the stone fragments directly instead of relying on their natural passage from the kidney.) For large stones, some type of energy device (ultrasound, a pneumatic drill-like device, or a special device called a holmium laser lithotriptor) may be needed to break the stone into small pieces. The holmium laser literally melts the stones and can be used on nearly all stone types. Of concern are studies reporting that the holmium laser produces cyanide as a by-product of uric acid stone fragmentation. No poisoning has been reported in any patient after this procedure, however, and the device has an excellent safety record. It should be used sparingly, however, and particularly cautiously with large uric stones until more is understood about this effect. Generally, patients stay in the hospital for five or six days and may need a small tube called a nephrostomy tube left in the kidney during the healing process.
Ureteroscopy. For stones in the lower tract, ureteroscopy is generally the best procedure although lithotripsy is also usually feasible and patients ordinarily prefer it. Ureteroscopy may be used for mid- and lower ureter stones. No incision is made in this procedure, but general anesthetic is still required. The surgeon passes a small fiberoptic instrument called a ureteroscope through the urethra and bladder into the ureter. The surgeon then locates the stone or stones. Smaller ones are grasped and removed with tiny forceps. Large ones are shattered with lasers or pneumatic drill-like devices. A small tube, or stent, may be left in the ureter for a few days after treatment to help the lining of the ureter heal.
Open Surgery (Nephrolithotomy). Standard open surgery (nephrolithotomy) is required if any of these procedures fail or are not appropriate, or in special cases, such as when the patient is very obese. Open surgery involves incisions through the patient's flank and into the kidney. The kidneys are cooled down using ice and x-rays are used during the procedure to locate specific areas and the stone. The arteries in the kidney are identified and isolated away from the surgical region. The surgeon locates the collecting system and retrieves the stone. If the surgeon finds any blockage, this is corrected. The surgery is very invasive and is now restricted to patients with very large or complex stones that cannot be removed using less invasive measures and very obese patients. The procedure is not appropriate for those with bleeding or clotting disorders, with untreated widespread infection, or with severe and chronic kidney insufficiency (unless removing the stone will improve kidney function).
More information on kidney stones
What are kidney stones? - Kidney stones are solid accretions (crystals) of dissolved minerals in urine found inside the kidneys or ureters. Also known as nephrolithiasis, urolithiasis or renal calculi.
What are kidney stones made of? - Kidney stones consist of a center that consists of crystal-like substances, and a surrounding region that is composed of layers. Kidney stones are composed of different chemical substances.
What are the symptoms of kidney stones? - Symptoms often occur when a stone migrates into the ureter, the tube that carries urine from the kidney to the bladder, and prevents the drainage of urine from the kidney.
What causes kidney stones? - The development of the stones is related to decreased urine volume or increased excretion of stone-forming components such as calcium, oxalate, urate, cystine, xanthine, and phosphate.
What are the risk factors for kidney stones? - Kidney stones affect about 12% of men and 5% of women by the time they are 70 years old. Kidney stones that strike women are more apt to occur during pregnancy.
How are kidney stones diagnosed? - Diagnosis of renal stone disease involves a medical history, physical examination, laboratory evaluation, and imaging tests.
What're treatment options for kidney stones? - Treatments of kidney stones include dietary modifications (including the advice to drink plenty of water), medications, and use of a lithotriptor.
What drug treatments are available for treatment and prevention of kidney stones? - Diuretics are commonly used in the treatment of high blood pressure and other disorders to eliminate fluid and sodium from the body. Citrate salts are often given to people with calcium oxalate or uric acid stones.
What dietary factors and lifestyle measures are used for prevention of kidney stones? - The most important recommendations for reducing the risk for calcium stones are increasing fluid intake, restricting sodium, and reducing protein intake.