For adults, ADPKD is a severe disease, but for children it used to be said that it’s asymptomatic,” says Charlotte Gimpel, MD, a pediatric nephrologist at Medical Center — University of Freiburg in Germany.
Doctors used to call autosomal dominant polycystic kidney disease (ADPKD) adult polycystic kidney disease. That’s because kids who carry one of two genes that cause it usually don’t feel sick. But ADPKD is a dominant genetic disease. Unlike many other conditions, it takes just one faulty copy of a gene to have ADPKD.
What that means is, for every child of a parent with the condition, the odds of APDKD are the same as the flip of a coin. A genetic test could give you the answer from birth or even before. But there’s a lot that an early gene test can’t tell you. That’s because ADPKD symptoms can vary a lot, even within the same family. Either way, the worst symptoms don’t show up until much later in life.
So while adults get huge kidneys and have a lot of pain until their kidneys fail and they need dialysis, children with ADPKD usually feel a lot less severe. It’s a misleading idea that kids with ADPKD don’t have any symptoms, though. Some kids already will have pain in their sides or back. They may have urinary tract infections (UTIs), kidney stones, or blood in the urine from cysts that already have started forming in the kidneys. Gimpel says kids may have trouble staying dry through the night if their kidneys aren’t working as well as they should.
“More children than we used to think get hypertension or proteinuria” (extra protein in their urine that’s an early sign of kidney damage), she says, “It doesn’t feel like you’re ill, but you can treat it.”
As doctors have begun to catch these early signs of ADPKD, they’ve started to change how they treat kids who may have the condition.
There’s no treatment to stop the cysts or future kidney problems. A drug to treat ADPKD is now approved for adults, but there’s still no way to treat ADPKD in kids. But doctors can help in other ways.
“If you leave them alone altogether, you miss the 20% who have a treatable condition,” Gimpel says. “You can’t really cure cystic disease, but treating hypertension is important for slowing progression [of kidney problems].”
Doctors are taking action earlier now that they can see warnings signs – if they notice a child starting to show symptoms, there are treatments that can help protect the kidneys and slow the disease’s progress.
ADPKD affects other parts of the body, too. Adults with it can have problems in the liver, pancreas, intestines, and heart. But, Gimpel says, there’s no sign these issues happen early in life, and kids don’t need extra screening.
You don’t need to be sure of ADPKD in a child to tackle early signs as they arise.