Advances in neonatal care are boosting survival rates of those born prematurely, but these survivors may later face kidney complications. New insights on how the kidney forms early in life and new tools to help monitor kidney development may one day help improve their health.
As the basic working units of the kidney, nephrons filter the blood, remove and eliminate urine, and help keep nutrients in the body. People have on average about 1 million nephrons per kidney, although the numbers may vary between individuals from 200,000 to about 2 million, said Marva Moxey-Mims, MD, chief of the division of nephrology at Children’s National Health System in Washington, DC.
Because nephron formation typically stops by 36 weeks of gestation, babies born earlier may not have a full complement of nephrons, said Moxey-Mims. Some nephrons may still be formed after birth, she noted, but far fewer than if gestation continued. Life-saving treatments, such as certain antibiotics, also may damage the nephrons these premature infants have, she noted.
“We can keep very, very early birth babies alive, but at a cost,” said Raphael Kopan, PhD, director of the division of developmental biology at Cincinnati Children’s. “The cost will be exacted when they are adults. They are at great risk for end stage renal disease.”
Recent findings from a study by Kopan and his colleagues suggest it may be possible to extend the production of nephrons early in life. These findings, along with emerging technologies to help clinicians count nephrons, may lead to new kidney-preserving strategies for both preemies and individuals with other forms of kidney disease.
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