Babies born with CHD likely to have enlarged kidneys

Research out of Australia suggests newborns with congenital heart disease (CHD) are likely to have enlarged kidneys at birth—a finding that could help alert physicians to organ abnormalities before a child is born.

The work, headed by Gemma Scholes of the University of Melbourne and published this week in Pediatric Research, is reportedly the first to investigate the link between babies’ congenital heart problems and their renal development. Scholes and her colleagues said it’s an important trial, since CHD is common at birth.

“It is known that the heart is not the only organ affected in CHD—there is growth restriction of both the brain and the whole body,” Scholes et al. wrote in the journal. “The protective mechanism of the ‘brain-sparing phenomenon’ redirects blood flow toward the growing brain in fetuses with CHD.”

When blood flow is prioritized to the brain in these cases, the authors said, it has adverse effects on other organs and the baby’s development.

Scholes and her team studied the phenomenon in 452 newborns, initially hypothesizing that children born with CHD would have smaller kidneys. But, after measuring ultrasounds taken before babies were operated on for the first time, the researchers found those with CHD had “significantly enlarged” kidneys, reaching an average length of 4.5 centimeters.

The extent of renal damage seemed to depend on the type of congenital abnormality, according to the study. Kids with left heart obstruction had larger kidneys than normal; children with cyanotic heart disease tended to have normal or enlarged kidneys. Even patients who suffered from a lack of amniotic fluid and were born smaller than average were likely to have larger kidneys.

“The kidneys of newborns with CHD are not reduced in size, and on average are larger than normal,” Scholes and co-authors wrote. “The nature of this size discrepancy and its subsequent clinical significance is unknown.”