Rocks for All Ages
Kidney stones, once an affliction found mainly in adults, are turning up in children. Nephrologists link salty diets and sodas to the trend.
|Sarah Abraham with Dr. Mehul Dixit of Florida Hospital|
Sarah Abraham had a “tummy ache” just before the school year began. Her parents, Carolyn and Sumner Abraham, assumed, as most parents would, that the pain was just nerves. But the stomach-ache persisted, eventually leading to a visit to the pediatrician. After ultrasounds and blood tests, and a trip to a specialist in Orlando for more tests, a diagnosis was reached that shocked the Abrahams.
Eight-year-old Sarah had a kidney stone.
Sarah’s diagnosis is part of a trend that has doctors in Central Florida, and around the nation, concerned. According to kidney specialists, the disease is escalating in children, though the number of cases is small overall. But like the Abrahams, of Port Orange, most parents are stunned to hear that their child has a kidney stone.
“A lot of times parents will say my son or daughter woke up, complained of pain, was vomiting, and the parent thinks it is appendicitis,” says Dr. Jorge A. Ramirez, director of pediatric nephrology at Arnold Palmer Hospital for Children. It’s not until tests such as X-rays or sonograms are done that they see the kidney stone.
Ramirez says he’s seen a 20 percent to 30 percent increase in children with stones in the past five years. Sarah’s specialist, Dr. Mehul P. Dixit, pediatric nephrologist and medical director of the Florida Hospital Pediatric Renal Transplant Program, agrees.
A diet high in salts seems to be the major culprit. In addition, kids don’t drink enough plain water or use the bathroom often enough.
Sarah is an active child who drinks water frequently, says her mother, but she also “loved her salty snacks.” Many children crave foods high in sodium, putting them on the fast track to a serious condition that used to occur only in adults.
“One of the tragedies of tough economic times is that often both parents need to work, making families more dependent on fast food,” says Dixit, who adds that sodium intake in young people has doubled in the past 20 years. Until parents can modify their lifestyles, it will be hard to cut back on salty processed food.
Consuming sports drinks and sodas instead of water is also a problem. Sports drinks are good when they are needed, to replenish electrolytes in athletes. But as a snack for inactive children, they contain too much salt.
“A bottle of Gatorade can contain enough salt for an entire day,” Dixit says.
Drinking sufficient water flushes the salt out of the system quickly, reducing the possibility of stone formation.
“Parents need to encourage children to drink lots of water, tap or bottled,” Dixit says.
Ramirez agrees: “Keeping a rapid flow through the urinary tract helps.”
Orange County Public Schools does not use salt in its recipes, says Lora Gilbert, food service director for the district, and a registered dietitian. The district also monitors the amount of sodium in food from suppliers.
“We have put an emphasis on fresh fruits and fresh and frozen vegetables,” Gilbert says. “We have not allowed carbonated beverages on school campuses for about a year.”
If parents wish to see the amounts of sodium in specific foods served in the cafeterias, they can make an appointment with food services to see the full nutritional descriptions, Gilbert says.
A kid eating unhealthy foods can consume an average of 4,000 to 5,000 milligrams of sodium per day, Dixit says, when all the body needs is about 1,700 mg. If a child consumes one sports beverage, some salt-filled processed food and a soda, the requirements are quickly surpassed. Excess salts, combined with a lack of water and little activity, can also lead to obesity, which some doctors say parallels the increase in stones.
Stones occur when substances in the urine—calcium and salts—crystallize in the small passageways in the kidneys. When children or adults take in extra salt it goes into the urine, pulling calcium along with it. The more salt intake, the more calcium pulled into the kidneys, the greater possibility of stones.
Even though the stones contain calcium, parents should not limit that mineral in a child’s diet, doctors say. Just have them drink sufficient water.
Parents also need to encourage their children to urinate more. Combine lack of water with too much salt intake and urine retention, and you are going to see an increase in stones.
Looking for Causes
Doctors are looking at other reasons besides diet for the uptick in numbers.
One is the survival, through advances in technology, of more and more extremely premature babies, who are given diuretics to relieve fluid in the lungs. The diuretics sometimes leave tiny kidney stones in the premature babies.
Other reasons include a genetic predisposition to excrete calcium, certain medications and abnormalities of the urinary tract.
However, parents need not panic. While the numbers are up, the incidence of kidney stones in children is pretty small overall. “Kidney stones appear in about five to 10 percent of the population,” Ramirez says. “Of that number, only five to 10 percent are children younger than 18.”
According to the Centers for Disease Control, about 1 million people are diagnosed with kidney stones each year, but fewer than one in 10,000 cases occur in someone under age 18. The CDC says the actual number is too small to be statistically accurate.
There was no family history of kidney stones in Sarah’s family, she was not obese, her back didn’t hurt and there was no blood in her urine. The tummy ache was and is the only symptom of the 2 millimeter stone that is lodged in her kidney.
Carolyn Abraham, 44, a homemaker, and Sumner Abraham, 43, a federal employee in law enforcement, now look very carefully at the foods Sarah eats.
"Sarah goes by the taste of her food and watches how much salt I put in when I’m cooking,” says Carolyn Abraham.
“I miss putting salt on my tomatoes and stuff, but I feel better knowing about this issue,” Sarah says. “It has made a change.”
The chips, pretzels and other salty snacks she used to love are no longer packed daily in her lunch. Instead she gets popcorn and fruit. She drinks more water than she had in the past.
And she waits for the kidney stone to pass.