A daily supplement of potassium citrate from the day children start the high-fat ketogenic diet to control epileptic seizures, researchers at Johns Hopkins Children's Center, will prevent excruciatingly painful kidney stones, which the diet may sometimes cause.
"We can confidently say this is a safe and powerful way to prevent kidney stones, and it should become part of standard therapy in all ketogenic dieters, not just those who already show elevated urine calcium levels. If you wait, it might be too late," says senior investigator Dr. Eric Kossoff, a pediatric neurologist at Hopkins Children's.
The ketogenic diet is believed to work by initiating biochemical changes that eliminate seizure-triggering short circuits in the brain's signalling system. It is given to many children whose seizures do not respond to medications.
However, the diet, which consists of high-fat foods with very few carbohydrates, causes a build-up of calcium in the urine and the formation of kidney stones in about 6 percent of those on it.
The researchers have revealed that two years after the children subjects had adopted the preventive treatment with potassium citrate, incidences of one major side effect of the diet reduced, allowing more children to remain on the diet for longer.
Potassium citrate taken twice daily, either as powder sprinkled on food or dissolved in water, is believed to inhibit stone formation.
The study involved301 children treated for epilepsy with the ketogenic diet at Hopkins Children's, and it showed that those who got potassium citrate twice daily were seven times less likely to develop kidney stones.
Although rarely serious, kidney stones can cause significant pain, along with kidney and urinary tract infections, and may require surgery.
A report on the work appears in the August issue of the journal Pediatrics.