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 not enough liquid, crystals can form into solids that can expand. Small stones can sometimes pass out of the body in the urine, but larger stones that are too big to pass can block urine flow in the kidney, ureter, bladder, or urethra, causing pain.
Kidney stones don’t always cause symptoms. Warning signs that may indicate you have a kidney stone include:
- Pain
- Occurs between the ribs and the hip (the flank) or the lower abdomen, and can move toward the groin
- Ranges from a mild ache to pain so intense it requires hospitalization
- Waves of severe pain called renal colic can last 20 minutes to an hour
- Pain can also be vague or feel like a stomach ache that doesn’t go away
- Pain may occur with urination
- Blood in the urine (hematuria)
- Urine may appear pink or reddish
- Gravel
- Passage of “gravel” or “sand,” which are multiple small stones in the urine
- Urinary urgency
- Foul-smelling urine
- Cloudy appearance to urine
- Nausea
- Vomiting
- Fever
- Chills
If you suspect you may have a kidney stone, see a doctor right away. You may be advised to drink additional fluids to try to flush a stone out in the urine. 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:
- Diet
- Inadequate fluid intake
- Diets high in animal proteins
- Consuming foods with excess salt or sugar (especially fructose, such as 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
- Obesity
- Weight loss surgery
- Infections
- Certain medical conditions
- Crohn's disease
- Diabetes mellitus
- Gout
- Primary hyperparathyroidism
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
- Ultrasound
- Computed tomography (CT) scan
- KUB x-ray (kidney-ureter-bladder X-ray)
- Blood tests
- Basic metabolic profile (BMP) which includes kidney function tests blood urea nitrogen (BUN) and creatinine
- Uric acid
- Calcium
- Phosphorus
- Pregnancy test
- Urine tests
- Urinalysis
- 24-hour urine test
What Is the Treatment for Kidney Stones?
Treatment for kidney stones depends on the size and location of the stone, the type of stone, and the patient’s pain levels.
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 may be recommended.
Home treatment for kidney stones includes:
- Pain management
- Medications to facilitate stone passage
- Straining urine to retrieve the stone for testing once it passes to help determine treatment
Medical treatments for larger stones or severe symptoms include:
- Prescription pain medication
- 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
- Shock wave lithotripsy (SWL)
- Percutaneous nephrolithotomy (PNL)
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https://www.uptodate.com/contents/kidney-stones-in-adults-beyond-the-basics?search=Kidney%20Stones&source=search_result&selectedTitle=3~150&usage_type=default&display_rank=3
https://www.kidney.org/atoz/content/kidneystones
https://www.kidney.org/news/kidneyCare/winter09/KidneyStoneSymptoms