Kidney Stones - What Happens

A kidney stone begins as a tiny piece of crystal in the kidney. When the urine leaves the kidney, it may carry the crystal out, or the crystal may stay in the kidney. If the crystal stays in the kidney, over time more small crystals join it and form a larger kidney stone.

Most stones leave the kidney and travel through the urinary tract when they are still small enough to pass easily out of the body. No treatment is necessary for these stones. But larger stones may become stuck in the tubes that carry urine from the kidney to the bladder ( ureters). This can cause pain and possibly block the urine from flowing to the bladder and out of the body. The pain often becomes worse over 15 to 60 minutes until it is severe. The pain may ease when the stone no longer blocks the flow of urine, and it often goes away when the stone passes into the bladder. Medical treatment is often necessary for larger stones.

• The smaller a stone is, the more likely it is to exit the body (pass) on its own. About 9 out of every 10 stones smaller than 5mm and about 5 out of every 10 stones 5mm to 10mm pass on their own. Only 1 or 2 out of every 10 kidney stones need more than home treatment.
• The average time a stone takes to pass ranges between 1 and 3 weeks, and two-thirds of stones that pass on their own pass within 4 weeks of when the symptoms appeared.Almost half of all people who get kidney stones will get more stones within 5 years unless they take preventive measures. When you have kidney stones several times over a period of years, the length of time between stones tends to get shorter. It is not possible to predict who will have more stones in the future and who will not.

Problems that may occur with kidney stones include:

• An increased risk of urinary tract infection, or making an existing urinary tract infection worse.
• Kidney damage, if stones block the flow of urine out of both kidneys (or out of one kidney, for people who have a single kidney). For most people with healthy kidneys, kidney stones do not cause serious damage until they completely block the urinary tract for 2 weeks or longer.

Kidney stones are more serious for people who have a single kidney or an impaired immune system or have had a kidney transplant.

How are kidney stones treated?

Fortunately, surgery is not usually necessary. Most kidney stones can pass through the urinary system with plenty of water (2 to 3 quarts a day) to help move the stone along. Often, you can stay home during this process, drinking fluids and taking pain medication as needed. The doctor usually asks you to save the passed stone(s) for testing. (You can catch it in a cup or tea strainer used only for this purpose.)

Kidney Stones - Home Treatment

Home treatment is often the only thing you need to do when passing a kidney stone. Home treatment includes drinking plenty of fluids, taking pain medicine, and possibly straining and collecting your urine to help determine the type of stone you have.

Drink extra fluids

You need to drink enough water to keep your urine clear, about 8 to 10 glasses of water a day when you are passing a kidney stone.

In some cases, you may need to avoid foods with high levels of oxalate, but your doctor can do tests that show whether this diet will help with your stones.

Use pain medicine

Medicine you can buy without a prescription, such as nonsteroidal anti-inflammatories (NSAIDs), may relieve your pain. NSAIDs include aspirin and ibuprofen (such as Motrin and Advil). Your doctor can prescribe stronger pain medicine if needed.

Collect kidney stones and urine

Your doctor may ask you to collect your kidney stone when it passes so that he or she can examine it to see what caused it to form.

• Your doctor will give you a strainer. Urinate through the strainer and save any stones, including those that look like sand or gravel. Continue to do this for 3 days after your pain stops.
• You can also urinate into a cup or container and empty the container through a strainer to collect the kidney stone. Strainers may be available at your local drugstore. You can also use coffee filters to strain urine.
• Allow the stones to dry, and store them in a plastic or glass container until you can take them to your doctor.

Your doctor may also ask you to collect your urine for 24 hours after you pass a stone, so he or she can check your urine to help determine the type and cause of the stone. Knowing the type of the stone may help you prevent getting stones in the future.

Kidney Stones - Other Treatment

If your pain is too great, the kidney stone is blocking the urinary system, or you also have an infection, your doctor will probably suggest medical treatment. Your options are:

• Extracorporeal shock wave lithotripsy (ESWL). This uses shock waves that pass easily through the body but are strong enough to break up a kidney stone. This is the most commonly used medical procedure for treating kidney stones.
• Ureteroscopy. The surgeon passes a very thin telescope tube (ureteroscope) up the urinary tract to the stone's location, and then he or she uses instruments to remove the stone or break it up for easier removal. Occasionally, you may need a small, hollow tube (ureteral stent) placed in the ureter to keep it open for a short time and drain urine and any stone pieces. This procedure is often used for stones that have moved from the kidney to the ureter.

The size of the stone, its location in the urinary tract, your overall health, and other factors are all considered in deciding which method to use when breaking up or removing a kidney stone.

Lifestyle Changes

A simple and most important lifestyle change to prevent stones is to drink more liquids—water is best. If you tend to form stones, you should try to drink enough liquids throughout the day to produce at least 2 quarts of urine in every 24-hour period.

People who form calcium stones used to be told to avoid dairy products and other foods with high calcium content. But recent studies have shown that foods high in calcium, including dairy products, may help prevent calcium stones. Taking calcium in pill form, however, may increase the risk of developing stones.

You may be told to avoid food with added vitamin D and certain types of antacids that have a calcium base. If you have very acidic urine, you may need to eat less meat, fish, and poultry. These foods increase the amount of acid in the urine.

To prevent cystine stones, you should drink enough water each day to dilute the concentration of cystine that escapes into the urine, which may be difficult. More than a gallon of water may be needed every 24 hours, and a third of that must be drunk during the night.

Foods and Drinks Containing Oxalate People prone to forming calcium oxalate stones may be asked by their doctor to cut back on certain foods if their urine contains an excess of oxalate: beets chocolate coffee cola nuts rhubarb spinach strawberries tea </LO> wheat bran People should not give up or avoid eating these foods without talking to their doctor first. In most cases, these foods can be eaten in limited amounts.

Prevention Points to Remember

• If you have a family history of stones or have had more than one stone, you are likely to develop more stones.
  
  
• A good first step to prevent the formation of any type of stone is to drink plenty of liquids—water is best.
  
  
• If you are at risk for developing stones, your doctor may perform certain blood and urine tests to determine which factors can best be altered to reduce that risk.
  
  
• Some people will need medicines to prevent stones from forming.
  
  
• People with chronic urinary tract infections and stones will often need the stone removed if the doctor determines that the infection results from the stone's presence. Patients must receive careful followup to be sure that the infection has cleared.