A kidney stone is a hard mass that develops in the kidneys as a result of separation of crystals from the urine. Kidney stones may be composed of a variety of different compounds and substances, but the most common type is called a calcium oxalate kidney stone.
Formation
Kidney stones form when the minerals, acids and fluid in the urine are out of balance. Calcium oxalate kidney stones form when there is an excess of oxalate in the body. When there is too much oxalate, it cannot be properly diluted by fluid and crystals, or stones, form. Oxalate can be consumed in the diet, but it is also produced by the liver.
Symptoms
According to MayoClinic.com, calcium oxalate kidney stones do not usually cause symptoms unless they have traveled into the ureter, which is the tube that carries urine from the kidneys to the bladder. When the kidney stone blocks the flow of urine, it can cause pain in the side, back, groin and abdomen. Other symptoms include painful urination, changes in urine color, nausea, vomiting and a frequent urge to urinate. If an infection develops, fever and chills may also occur.
Treatment
Kidney stones usually pass through the urinary system and out of the body without any medical intervention. An increase in fluid intake to 2 to 3 quarts per day can help with this passage, according to the National Kidney and Urologic Diseases Information Clearinghouse. Over-the-counter pain medications can help reduce pain while waiting for the kidney stone to pass.
Surgery to remove the stone may be necessary if the stone does not pass on its own, is too large to pass on its own, grows in size, completely blocks urine flow, causes intense pain or causes a urinary tract infection.
Complications
If left untreated, a kidney stone can lead to a decreased or complete loss of function of the affected kidney, according to Medline Plus. The stone can also irritate the kidney, which results in scarring and damage to the kidney.
Foods to Avoid
If you are prone to developing calcium oxalate kidney stones, it can be beneficial to avoid foods that contain oxalate. Foods that are considered high-oxalate include spinach, beets, Swiss chard, peanuts, chocolate, sweet potatoes, rhubarb and wheat germ. Foods that are considered medium-oxalate include grits, grapes, celery, green peppers, raspberries, strawberries and liver, according to the National Kidney and Urologic Diseases Information Clearinghouse.
