Based on specific body chemistry, the human body can make 16 different kidney stones and there are 24 reasons why it may create them, so those wondering how to prevent or avoid them should see a urologist.

That's one piece of advice offered Saturday to callers as part of the Deseret News/Intermountain Healthcare Hotline. More than two dozen callers from all along the Wasatch Front, as well as Florida and Texas, sought free advice from Dr. Jay Bishoff, a urologist and medical director of the Intermountain Urological Institute at Intermountain Medical Center, and his colleague at the institute, Dr. Scott Chidester, also a urologist.

The two specialists fielded questions about kidney cancer, prostate cancer, kidney stones and incontinence — "roughly the range of issues we see in our practice," Chidester said. "Most were looking for second opinions or had questions" about treatment.

Several callers who have had previous kidney stone episodes asked how to prevent them. Both specialists agreed that a low-sodium, low-protein diet and drinking lots of fluids helps for many patients, but because there are so many reasons why the stones develop and so many varieties, there's no one set of recommendations that works for everyone.

"We tell them they need to find the exact problem that could be causing" the body to manufacture the stones," Chidester said, and because it involves body chemistry specific to the individual patient, urologists must see them to determine an individual approach to the problem.

"If there is a family history of kidney stones, you are 30 times more likely to have them yourself," Bishoff said. "There are things we can do to prevent stones, but nothing you can do to prevent all stones."

"Some people need to take calcium," which seems disingenuous, he said, because many people believe the stones are the result of too much calcium in the diet. "Some need to stop eating huge amounts of protein," cutting out the large prime rib or other large cuts of meat.

"People often say, 'If I do this or that can I prevent them,' but unless we do a daily urine collection and analyze it for risk factors, we're really just guessing," Bishoff said.

About 90 percent of the time, doctors can determine through analyzing the urine over a 24-hour period why a particular patient is creating a particular type of stone.

"Unless we do that, we have no idea why they made that stone," Bishoff said, adding that about 95 percent of procedures to eliminate kidney stones involve outpatient surgery to break up the stone so it can pass through the system.

One hotline caller recently had surgery for a rare type of kidney cancer and was wondering what to expect in the future. Another was experiencing kidney problems in addition to a complicated pregnancy and was seeking advice on when and how to be treated.

Several people also e-mailed questions, which will be summarized for the specialists answer. Those responses will be posted online Friday at