What are kidney stones?

Kidney stones (nephrolithiasis or urolithiasis) are not an uncommon health issue. Approximately 12% of men and 5% of women are affected by age 70. A kidney stone forms when patients have high levels of calcium, oxalate, cystine or uric acid in the urine. However, stones can also form when these substances are at normal levels if the amount of urine a patient produces each day is low. These substances form crystals, which become lodged in the kidney and gradually build in size, creating a kidney stone. Symptoms include flank (side between rib and hip) pain, blood in the urine, “gravel” or small stones in the urine, vomiting and pain with urination.

Usually, the stone will move through the urinary tract and pass 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 medication to help speed passage or a procedure or surgery to remove them.

What factors contribute to kidney stones?

Disease states that contribute to an increased risk of developing kidney stones include gout, diabetes, Crohn’s disease, obesity and gastric bypass surgery. Other factors include not drinking enough fluids, a diet with low levels of calcium, use of calcium supplements, a diet with high levels of animal protein, a diet high in sugar and sodium.

What is kidney failure?

Kidney failure has different causes. It can happen when less blood than usual flows to the kidneys. Different things can cause this to happen. For example, if a patient has heart failure, the heart might not be able to pump enough blood to the kidneys. The kidneys get damaged. Causes of kidney damage include infections, cancer, certain medicines, and particular autoimmune conditions (this is when a person’s immune system attacks his or her body). The path the urine takes to leave the body is blocked. In men, some causes of blockages are prostate issues. Some patients may not have symptoms at first, but it they do, symptoms include urinating less or not at all, blood in the urine, swelling in the legs or feet, vomiting, feeling week, and confusion.

Kidney stones are not the same thing as kidney failure.

But, as you can see, since there are some similar symptoms for both kidney stones and kidney failure so it is important that you contact your primary care provider immediately if you have any of these symptoms for a complete evaluation.

Alan Benvenisty, MD, is the Director of the Renal Transplant Program at Mount Sinai St. Luke’s and Mount Sinai Roosevelt.