Kidney Stone Disease
Kidney Stone Disease is the most common urologic disorder, with an estimated 720,000 Americans affected yearly. The majority of cases occur in people between the ages of 20 and 40, and it is more common in men, who account for about 4 out of 5 cases. Kidney stones are hardened mineral deposits that form in the kidneys. There are four main types of kidney stones: calcium , uric acid, struvite, and cystine.
As stones are formed, they may vary in size, some may be passed natuarally, while larger stones could potentially block the flow of urine or irritate the lining of the urinary tract. These larger stones may require surgery or to be broken down into smaller pieces using a stone-crushing method called lithotripsy.
For patients that have passed their first kidney stone, it is very difficult to predict the likelihood of recurrence. Seventy percent of patients who pass one stone will have another within 10 years. However, patients with severe disease may have multiple stones occurring monthly or more often. Many stones will recur within 5-7 years, with a larger number peaking at two years. As kidney stone patients age, their rate of new stone formation appears to decline, and remissions are common after the age of 50.
Your physician will help you determine what type of stone you may have, ways to keep existing stones from getting larger, how to treat your stones, and how to prevent future stones from forming.
Q: What is a kidney stone?
A: Kidney stones (calculi) are hardened mineral deposits that form in the kidneys. The kidneys filter waste products from the blood and add them to the urine that they kidneys produce. When salts or minerals normally found in the urine do not dissolve completely, they crystallize in the kidney forming kidney stones. In most cases, the crystals are so small that they are passed through the body harmlessly. However, they can build up inside your kidney and form much larger stones. Some of these larger stones may travel to other parts of the urinary tract, including the ureter or the bladder.
Q: Am I at risk?
A: Factors that will contribute to stone formation will vary depending on the type of stone. Overall though, men are more likely to develop kidney stones than women. Also about half of all people who experience a kidney stone will develop another one within 5 years. Other risk factors that can contribute to stone formation are:
- Family history of kidney stones
- Being aged between 20 and 40
- Diets high in calcium (dairy products), protein or oxalates (colas, chocolate)
- Making certain medicines such as diuretics, antacids and thyroid medications
- Urinary tract blockage or chronic urinary tract infections
- Too little fluid intake
- Limited activity for several weeks
Q: What are the symptoms?
A: Although kidney stones may cause different levels of symptoms, depending on their location, size, and shape, the sudden severe pain associated with passing a stone is an event that most patients will not soon forget. Some people may not have any symptoms, but most experience at least some of the following:
- Severe pain in the kidneys or lower abdomen, which may move to the groin; pain may last for minutes or hours , followed by periods of relief.
- Nausea and vomiting
- Fever, chills and weakness
- Cloudy or foul-smelling urine
- Blood in the urine
- Blocked flow of urine
Q: How is a kidney stone detected?
A: Doctors can usually diagnose kidney stones by inquiring about your symptoms and conducting a physical examination. Further tests may be run to confirm the diagnosis and define the size, location and type of stone. X-rays can usually identify the presence of stones, while specialized x-ray techniques o sound waves may be used to identify more accurately the size and location of the stones and to test kidney function. Blood and urine tests may help the doctor discover what is causing the stone formation and plan the best treatment option for the patient.
Q: Do I have a choice of treatment?
A: Yes. Treatment depends on the type of stone you have, your diagnostic test results and your medical history. Most stones can be treated without surgery by increasing fluid intake, changes in diet, medication and physical activity levels. About 90% of stones will pass by themselves within 3 to 6 weeks. Stones that do not pass my need to be removed through surgical intervention. A new method of stone removal is called extracorporeal shock wave lithotripsy. During this procedure, stones are broken down into small fragments by high energy shock waves from a device outside the body.
Your physician will determine an appropriate treatment program, depending on the type of stone you have formed. As always, it is important for you to discuss thoroughly the various treatment options with your doctor.