Kidney stones (nephrolithiasis or urolithiasis) are hard objects formed from substances in the urine. Waste products usually dissolve in urine, but sometimes if there is excess waste and insufficient liquid, crystals can form into solids that grow.
Small stones may be passed out of the body in the urine, but larger stones too big to pass can block urine flow in the kidney, ureter, bladder, or urethra, causing the pain of kidney stones.
15 Signs & Symptoms of Kidney Stones
- Occurs on the side, between the ribs and the hip (the flank) or the lower abdomen, and can migrate toward the groin
- Varies from a mild ache to intense pain that requires hospitalization
- Waves of severe pain (renal colic) that can last 20 minutes to an hour
- Pain can also be vague or feel like a stomach ache that doesn’t go away
- Pain with urination
- Blood in the urine (hematuria)
- Urine may appear pink or reddish
- Passage of “gravel” or “sand,” which are multiple small stones in the urine
- Urinary urgency
- Foul-smelling urine
- Cloudy appearance to urine
If you think you are getting a kidney stone, see a doctor right away. Drinking additional fluids to try to flush a stone out in the urine may be recommended. If a stone does pass, it is helpful to strain it and bring it to your doctor to determine what kind of stone it is.
What Causes Kidney Stones?
Causes of kidney stones include:
- Not drinking enough fluids
- Diets high in animal proteins
- Consuming foods with excess salt or sugar (especially fructose, like table sugar and high fructose corn syrup)
- Use of calcium supplements
- Diets low in calcium
- Diet with low levels of phytate (found in wheat, rice, rye, barley, and bean products)
- Frequent spinach consumption
- Family history of kidney stones
- Too much or too little exercise
- Weight loss surgery
- Certain medical conditions
How Are Kidney Stones Diagnosed?
Kidney stones are diagnosed based upon a patient’s symptoms and physical examination, along with tests to confirm a stone or rule out other conditions.
Tests used to diagnose kidney stones include:
- Imaging tests
- Computed tomography (CT) scan
- KUB x-ray (kidney-ureter-bladder X-ray)
- Blood tests
- Urine tests
- 24-hour urine test
After the stone comes out of the body, either on its own or following surgical removal, it can be analyzed to determine the type of stone and treatment.
What Is the Treatment for Kidney Stones?
Treatment of a kidney stone depends on the size and location of the stone, the type of stone, and the patient’s pain levels.
Home treatment may be recommended if the stone is believed to be small enough to pass, the patient’s pain is tolerable, and they can eat and drink.
Home treatment for kidney stones includes:
- Pain management
- Medications to facilitate stone passage
- Straining urine to retrieve the stone for testing once it passes
- Knowing the type of stone you have helps determine treatment to prevent future stones
Medical treatments for larger stones or severe symptoms include:
- Stronger prescription pain medications
- Intravenous (IV) fluids given in the hospital
- Stones larger than 9 or 10 millimeters usually do not pass on their own so a procedure is needed to break up or remove the stone
- Ureteroscopy uses a thin telescope passed through the urethra and bladder into the ureter and kidney to remove the stone or to break it into smaller pieces that can pass more easily
- Shock wave lithotripsy (SWL) directs high-energy shock waves toward the stone causing the stone to fragment and be more easily passed in the urine
- Percutaneous nephrolithotomy (PNL) is a minimally invasive surgical procedure in which a small telescope is passed through the skin of the back and into the kidney to remove the stone