The kidneys are a pair of organs located in the back of the abdomen. Each kidney is about the size of a fist. The primary function of the kidneys is to filter waste from the blood. This waste is then passed out of the body as urine. This is normally performed several times a day with no problems in a healthy person. Sometimes, however, small mineral and acid salts may crystallize in the kidney, forming a stone. Passing a kidney stone through the urinary tract may be extremely painful and in severe cases may require surgical intervention.
There is not one specific cause of kidney stones, partially because there is not one specific type of kidney stone. Some stones are composed of calcium deposits, some are composed of uric acid crystals, while others form in response to infection. Patients with a family history of kidney stones are more likely to develop stones of their own, and patients who have previously had kidney stones are at an increased risk of developing more. Dehydration, excessive sweating, poor dietary choices (particularly diets high in sodium), obesity, and certain digestive diseases also increase a patient’s likelihood of developing kidney stones. While there is no fool-proof method for avoiding kidney stones, drinking plenty of water, eating a diet low in sodium and low in animal protein, and limiting your amount of foods rich in a calcium-type substance called oxalate (such as deep green leafy vegetables, sweet potatoes, soy, nuts, and chocolate) may help prevent these painful deposits. If you have previously had kidney stones, your doctor may prescribe medications that specifically target and prevent the stones you are at the highest risk for.
The most commonly recognizable sign of kidney stones is pain in the side or back, just below the ribs. This pain may come in waves and differ in intensity through the day, including becoming more severe during urination. Kidney stone pain may also radiate to the lower abdomen or groin area. A patient may also notice changes in their urination habits or in the urine itself. A patient with a kidney stone may have to urinate more frequently, though he/she may not produce much urine at one time. The urine itself may look unusual – it may have a cloudy appearance or be pink, red, or even brown in color. It may smell foul. Contact your doctor if you experience any of these symptoms. Seek emergency medical attention if you notice blood in your urine, experience pain so severe that you cannot sit down or get comfortable, or if your pain is accompanied by fever, chills, nausea, or vomiting.