My daughter came home from preschool the other day and told me that "Sadie" was sick. "She has a kidney stone," my daughter told me. As a good parent, I nodded my head and showed sympathy while thinking, "Could that really be possible? Did my daughter hear someone talking about kidney stones and conflate two experiences?" Well, probably not, based on new evidence reported in the New York Times.
To the great surprise of parents, kidney stones, once considered a disorder of middle age, are now showing up in children as young as 5 or 6. While there are no reliable data on the number of cases, pediatric urologists and nephrologists across the country say they are seeing a steep rise in young patients. Some hospitals have opened pediatric kidney stone clinics. “The older doctors would say in the ’70s and ’80s, they’d see a kid with a stone once every few months,” said Dr. Caleb P. Nelson, a urology instructor at Harvard Medical School who is co-director of the new kidney stone center at Children’s Hospital Boston. “Now we see kids once a week or less.”
Why are kidney stones on the rise in kids? Doctors think that, like adults, kids who eat too much salt and don't drink enough water are at an increased risk.
Forty to 65 percent of kidney stones are formed when oxalate, a byproduct of certain foods, binds to calcium in the urine. (Other common types include calcium phosphate stones and uric acid stones.) And the two biggest risk factors for this binding process are not drinking enough fluids and eating too much salt; both increase the amount of calcium and oxalate in the urine.... “What we’ve really seen is an increase in the salt load in children’s diet,” said Dr. Bruce L. Slaughenhoupt, co-director of pediatric urology and of the pediatric kidney stone clinic at the University of Wisconsin. He and other experts mentioned not just salty chips and French fries, but also processed foods like sandwich meats; canned soups; packaged meals; and even sports drinks like Gatorade, which are so popular among schoolchildren they are now sold in child-friendly juice boxes.