KIDNEY STONES

As the kidneys filter waste from the blood, they create urine. Sometimes, salts and other minerals in urine stick together to form small kidney stones. These range from the size of a sugar crystal to a ping pong ball, but they are rarely noticed unless they cause a blockage.  Medically, this is called nephrolithiasis.

Kidney stones form when there is a decrease in urine volume or an excess in stone-forming substances in the urine.  Dehydration or strenuous exercise without adequate fluid replacement increases the risk of kidney stones.  Infection can also lead to the production of a type of kidney stone, called the struvite stones.

They may cause intense pain if they break loose and push into the ureters, the narrow ducts leading to the bladder.  Depending on your situation, you may need nothing more than to take pain medication and drink lots of water to pass a kidney stone.

Knowing each type of kidney stone may help determine the cause and may give clues on how to reduce your risk.  Types of kidney stones include:

  • Calcium stones. Most kidney stones are calcium stones, usually in the form of calcium oxalate. Dietary factors, high doses of vitamin D, intestinal bypass surgery and several metabolic disorders can increase the concentration of calcium or oxalate in urine.
  • Struvite stones. Struvite stones form in response to an infection, such as a urinary tract infection.
  • Uric acid stones. Uric acid stones can form in people who don’t drink enough fluids or who lose too much fluid, those who eat a high-protein diet, and those who have gout.
  • Cystine stones. These stones form in people with a hereditary disorder that causes the kidneys to excrete too much of certain amino acids (cystinuria).
  • Other stones. Other, rarer types of kidney stones also can occur.

A kidney stone may not cause symptoms until it moves through the urinary tract, by that point they may cause:

  • Severe pain in the side and back, below the ribs
  • Pain that spreads to the lower abdomen and groin
  • Pain that comes in waves and fluctuates in intensity
  • Pain on urination
  • Pink, red or brown urine
  • Cloudy or foul-smelling urine
  • Nausea and vomiting
  • Persistent need to urinate
  • Urinating more often than usual
  • Fever and chills if an infection is present
  • Urinating small amounts of urine

Small stones may pass without causing symptoms.

DIAGNOSIS

The diagnosis of kidney stones is suspected when the typical pattern of symptoms is noted and when other possible causes of the abdominal or flank pain are excluded.  Kidney stones are rarely diagnosed before they begin causing pain. This pain is often severe enough to send patients to the ER, where a variety of tests can uncover the stones. These may include:

  • Blood testing. Blood tests may reveal too much calcium or uric acid in your blood.
  • Urine testing. The 24-hour urine collection test may show that you’re excreting too many stone-forming minerals or too few stone-preventing substances.
  • Imaging. Imaging tests may show kidney stones in your urinary tract. Options range from simple abdominal X-rays to high-speed or dual energy computerized tomography (CT).
Other imaging options include an ultrasound, a noninvasive test, and intravenous urography, and taking X-rays (intravenous pyelogram) or obtaining CT images (CT urogram) as the dye travels through your kidneys and bladder.
  • Analysis of passed stones. You may be asked to urinate through a strainer to catch stones that you pass. Lab analysis will reveal the makeup of your kidney stones. Your doctor uses this information to determine what’s causing your kidney stones and to form a plan to prevent more kidney stones.

 

RECOMMENDED MEDICATIONS

Treatment for kidney stones varies, depending on the type of stone and the cause.

Small stones with minimal symptoms

Most kidney stones won’t require invasive treatment. You may be able to pass a small stone by:

  • Drinking water. Drinking as much as 2 to 3 quarts (1.9 to 2.8 liters) a day may help flush out your urinary system.
  • Pain relievers. To relieve mild pain, your doctor may recommend pain relievers such as ibuprofen (Advil, Motrin IB, others), acetaminophen (Tylenol, others) or naproxen sodium (Aleve).
  • Medical therapy. Your doctor may give you a medication to help pass your kidney stone. This type of medication, known as an alpha blocker, relaxes the muscles in your ureter, helping you pass the kidney stone more quickly and with less pain.

Large stones and those that cause symptoms

Kidney stones that can’t be treated with conservative measures — either because they’re too large to pass on their own or because they cause bleeding, kidney damage or ongoing urinary tract infections — may require more extensive treatment. Procedures may include:

  • Using sound waves to break up stones. For certain kidney stones — depending on size and location — your doctor may recommend a procedure called extracorporeal shock wave lithotripsy (ESWL).
ESWL uses sound waves to create strong vibrations (shock waves) that break the stones into tiny pieces that can be passed in your urine.
  • Surgery to remove very large stones in the kidney. A procedure called percutaneous nephrolithotomy involves surgically removing a kidney stone using small telescopes and instruments inserted through a small incision in your back.
  • Using a scope to remove stones. To remove a smaller stone in your ureter or kidney, your doctor may pass a thin lighted tube (ureteroscope) equipped with a camera through your urethra and bladder to your ureter.
  • Parathyroid gland surgery. Some calcium phosphate stones are caused by overactive parathyroid glands, which are located on the four corners of your thyroid gland, just below your Adam’s apple.

Related Articles

TETRALOGY OF FALLOT

Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Tetralogy of Fallot is a congenital heart defect that affects the [...]

TRICHINOSIS

Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Trichinosis, also known as trichinellosis, is a parasitic infection caused by [...]

TRIGEMINAL NEURALGIA

Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Trigeminal neuralgia is a neurological condition characterized by severe facial pain. [...]