Kidney Disease No Longer a Killer for Children
But research could help survivors live longer, healthier lives
WEDNESDAY, June 23, 2004 (HealthDayNews) -- Fifty years ago, nearly all children born with severe forms of kidney disease simply waited to die. The advent of dialysis and kidney transplants changed all that, however, and most kids with the illness now live long, productive lives.
But experts say there's more that can and should be done.
"Even kidney transplantation does not restore kidney function entirely to normal," said Australian researcher Stephen McDonald, lead author of a study published in the June 24 issue of the New England Journal of Medicine.
Subpar kidney function increases risks for cardiovascular trouble over the long term, McDonald explained, while powerful immune-suppressing drugs used to fight organ rejection raise a child's risk for infections and even cancer.
Overall, the study found that people who survived severe kidney disease as children still faced a 30-fold higher risk of death as adults, compared to individuals with no history of kidney problems.
Kidney failure affects about 250 to 300 adults out of every 1 million, and is usually attributed to systemic chronic illness such as diabetes or cardiovascular disease. The condition is much more rare in children -- about five or 10 cases per million -- and is most often linked to congenital malformations of the kidneys or bladder.
McDonald works at the Australia and New Zealand Dialysis and Transplant Registry at Queen Elizabeth Hospital, in Adelaide. He and his colleagues analyzed the medical records all 1,634 children with severe, end-stage kidney disease, tracked by the registry between 1963 and early 2002.
Most of the children -- 1,398 -- received one or more kidney transplants as part of their therapy.
Overall, the study found that 79 percent of children who received either long-term dialysis or new kidneys were still alive 10 years after their transplant, with that number dropping to 66 percent at 20 years post-transplant.
Cardiac problems were the leading cause of death, followed by infection, and children who received dialysis were at higher risk of dying than those who underwent a transplant.
But McDonald stressed that the history of research into pediatric kidney disease is largely one of successes, not failures.
"With respect to dialysis, there have been important technological advances, which means that the process is now more efficient and safer than previously," he said. "Control of blood pressure and other metabolic complications is better with new drugs. With respect to transplantation, the major changes have been related to immunosuppressive [anti-rejection] drugs, which have greatly prolonged the survival of kidney transplants."
Other advances now allow doctors to catch kidney disease before a child is even born.
"The ability to diagnose congenital kidney malformations in the uterus with the use of ultrasound has greatly impacted many patients who would otherwise have developed kidney failure," pointed out Dr. Leslie Spry, a nephrologist at the Dialysis Center of Lincoln, in Lincoln, Neb., and a spokesman for the National Kidney Foundation.
"Getting pediatricians and family physicians to focus on kidney disease when there is family history of disease is important," he said.
Most important, a rise in the number of living individuals willing and able to donate a kidney to help an ailing child has greatly improved survival rates. According to the study, between 1963 and 1972 just 5 percent of transplanted kidneys in Australia and New Zealand came from living donors. That number rose to 35 percent for the decade spanning 1983 to 1992 and to 64 percent in the last 10 years of the study -- 1993 to 2002.
In fact, most children who need a kidney today "are transplanted reasonably early," said National Kidney Foundation spokesman Dr. William Harmon, director of the division of nephrology at Children's Hospital Boston.
"The majority have living donors, which are preferable and which can be used preemptively," he said. Furthermore, children who depend on transplants from non-living donors "get priority over adults," Harmon said. "The system provides them benefit."
Still, long-term problems associated with pediatric kidney disease mean too many patients will die too early from kidney-related diseases as they age. Most experts agree that more research needs to be done in preventing childhood kidney dysfunction and in finding better, less harmful methods of suppressing organ rejection.
"We need to get to immune intolerance [of transplanted organs] and we are not there yet with our medical management, post-transplantation," Spry said.
Learn about kidney disease and how to become an organ donor by visiting the National Kidney Foundation.