KIDNEY STONES OVERVIEW
Kidney stones (also called nephrolithiasis or urolithiasis) affect approximately 12 percent of men and 5 percent of women by age 70. Fortunately, treatment is available to effectively manage most stones. In addition, you can take steps to prevent kidney stones from recurring.
HOW KIDNEY STONES DEVELOP
A kidney stone can form when substances such as calcium, oxalate, cystine, or uric acid are at high levels in the urine. Stones can also form if these substances are at normal levels. The substances form crystals, which become anchored in the kidney and gradually increase in size, forming a kidney stone. Typically, the stone will move through the urinary tract and is passed out of the body in the urine. A stone may cause pain if it becomes stuck and blocks the flow of urine. Large stones do not always pass on their own and sometimes require a procedure or surgery to remove them.
KIDNEY STONE SYMPTOMS
Pain — Pain is the most common symptom of kidney stones. Pain can range from a mild and barely noticeable ache to discomfort that is so intense it requires treatment in the hospital. Typically, the pain gets worse and better, but does not go away completely. Waves of severe pain, known as renal colic, usually last 20 to 60 minutes. Pain can occur in the flank (the side, between the ribs and the hip) or the lower abdomen.
Blood in the urine — Most people with kidney stones will have blood in the urine (hematuria). The urine may be pink or reddish, or the blood may be visible only with urine dipstick testing or microscopic examination of the urine. You may pass "gravel" or small stones in your urine.
Other symptoms — Other kidney stone symptoms include nausea or vomiting, pain with urination, and an urgent need to urinate.
Asymptomatic kidney stones — Many people with kidney stones have no symptoms (asymptomatic means without symptoms). These kidney stones are usually found when an imaging study (such as an ultrasound, x-ray or CT scan) is performed is done for other purposes. Stones can remain in the kidneys for many years without ever causing symptoms.
KIDNEY STONE DIAGNOSIS
Kidney stones are usually diagnosed based upon your symptoms, a physical examination, and imaging studies.
Computed tomography (CT) scan — A CT scan creates a three dimensional image of structures within the body. A particular type of CT scan (called noncontrast helical CT) is often recommended if kidney stones are suspected.
Ultrasound — An ultrasound can also be used to detect kidney stones, although small stones or stones in the ureters may be missed. However, ultrasound is the procedure of choice for people who should avoid radiation, including pregnant women.
KIDNEY STONE TREATMENT
Treatment of kidney stones depends upon the size and location of your stone, as well as your pain and ability to keep down fluids. If you stone is likely to pass, your pain is tolerable, and you are able to eat and drink, you can be treated at home. If you have severe pain or nausea, you will need to be treated with stronger pain medications and IV fluids, which are often given in the hospital.
