Health & Medicine

Why kidney stones form and how you can prevent them

Dr. John Tuttle is an urologist with KentuckyOne Health Urology Associates
Dr. John Tuttle is an urologist with KentuckyOne Health Urology Associates

Anyone may develop a kidney stone. However, there are steps to take to prevent kidney stone formation.

First, it's important to understand what exactly the kidney does and why kidney stones exist. The kidney normally excretes body wastes and chemicals before they build up to become poisonous. Kidney stones result when chemicals settle out within the kidney itself forming a concretion or stone.

Kidney stones form when this chemical precipitates out of solution and in turn crystals attach themselves to the kidney tissue. From there the process continues to add more and more layers and thus the stone grows or gets larger.

Such kidney stones can become dislodged and then float with the urine downstream toward the urinary bladder. The stones can become lodged in the small tubes, blocking the flow of urine and thus building back pressure, which stretches the capsule of the kidney where pain fibers are located and cause severe back and flank pain.

Some kidney stones can harbor bacteria and are infected stones leading to recurrent urinary tract infections. Stones can damage the kidney tissue and lead to kidney scarring and eventual failure of the kidney to properly clear the poison from the body. This is called renal failure.

Each person has a unique reason or reasons for stones. Kidney stones are common in certain families and are therefore genetically determined. The kidney actually produces chemicals, which restarts stone formation.

The amount of stone inhibitor a person generates is gene-determined. A person who makes a normal amount of inhibitor may rarely or never make kidney stones. Another person who makes less stone inhibitor may occasionally make a kidney stone. Still another person who makes very little inhibitor may make many stones.

Other stones occur because a person does not drink enough fluid, which makes the urine more concentrated and therefore more likely to start the crystal formation. Inflammatory bowel disease, excessive vitamin use, antacids for stomach ulcers, too much table salt use, and eating too much meat are risk factors attributed to kidney stone formation.

Basic steps in stone prevention are to drink enough fluids that one voids more than two quarts urine daily and reducing the amount of table salt and meats in the diet.

To be more specific as to why an individual makes kidney stones requires periodic blood tests and 24-hour urine collections. Analysis of concentrations of stone inhibitors, such as citrate and magnesium, and urine concentrations of calcium, uric acid, phosphorous, sodium, pH, and volume are instrumental in tailoring an individual stone prevention program.

Preventing kidney stones requires a lifelong compliance commitment from the patient and provider.