Kidney and Bladder stones

Kidney or bladder stones are solid build-ups of crystals made from minerals and proteins found in urine. Bladder diverticulum, enlarged prostate, neurogenic bladder and urinary tract infection can cause an individual to have a greater chance of developing bladder stones.

If a kidney stone becomes lodged in the ureter or urethra, it can cause constant severe pain in the back or side, vomiting, hematuria (blood in the urine), fever, or chills.

If bladder stones are small enough, they can pass on their own with no noticeable symptoms. However, once they become larger, bladder stones can cause frequent urges to urinate, painful or difficult urination and hematuria.

Stones are made of minerals in the urine that form crystals. Sometimes the crystals grow into stones. About 85% of the stones are composed of calcium, and the remainder are composed of various substances, including uric acid, cystine, or struvite. Struvite stones—a mixture of magnesium, ammonium, and phosphate—are also called infection stones, because they form only in infected urine.

How are kidney and bladder stones diagnosed and evaluated?

Imaging is used to provide your doctor with valuable information about the kidney or bladder stones, such as location, size and effect on the function of the kidneys. Some types of imaging that your doctor may order include:

• Abdominal and pelvic CT: This is the most rapid scanning method for locating a stone. This procedure can provide detailed images of the kidneys, ureters, bladder and urethra, identify a stone and reveal whether it is blocking urinary flow. See the Safety page for more information about CT procedures.
• Intravenous pyelogram (IVP): This is an x-ray examination of the kidneys, ureters and urinary bladder that uses iodinated contrast material injected into veins to evaluate the urinary system. See the Safety page for more information about x-rays.
• Abdominal and Pelvic ultrasound: These exams use sound waves to provide pictures of the kidneys and bladder and can identify blockage of urinary flow and help identify stones.

How are kidney and bladder stones treated?

If a stone blocks urine flow and drainage of the kidney, there are a variety of possible treatments. An option that your doctor may choose is:

• Ureteral stenting or nephrostomy: A ureteral stent is a thin, flexible tube threaded into the ureter by a urologist to restore the flow of urine to the bladder from the kidney.

• A nephrostomy is performed by an interventional radiologist when ureteral stenting is not possible or desirable. A tube is placed through the skin on the patient's back into the kidney and the tube is connected to an external drainage bag. The procedure is usually performed with fluoroscopy.