Breast milk ingredient could end infant deaths
5/7/2013PITTSBURGH — It’s one of the unsolved mysteries in modern medicine: a stomach condition that strikes the tiniest of babies with potentially devastating consequences.
For years, doctors have known that necrotizing enterocolitis occurs much less frequently with babies who are fed exclusively breast milk instead of formula.
Researchers at the University of Pittsburgh and Children’s Hospital of Pittsburgh of UPMC now think that they understand why — and have found promising results in treating mice.
“It’s one of the last few enigmas,” said David Hackam, co-director of the Fetal Diagnosis and Treatment Center at Children’s Hospital and senior author of the study. “It’s so frustrating. You have these babies, they seem to be doing well, and it happens out of the blue.”
The study was published online Monday in the Proceedings of the National Academy of Sciences.
It found that premature babies have higher amounts of an immune protein called TLR4 than full-term babies.
That surplus leads to a reduction in nitric oxide, which narrows blood vessels and decreases blood flow, leading to tissue death.
By adding sodium nitrate to formula fed to premature mice, the researchers were able to correct the blood flow, leading to dramatically lower incidences of NEC in the mice.
Sodium nitrate naturally occurs in high levels in breast milk but is not a component in infant formula, said Dr. Hackam, in part because of concerns about a link between nitrate consumption and gastrointestinal cancer.
The findings in the study are “important and plausible,” said Ardythe Morrow, director of the Center for Interdisciplinary Research in Human Milk & Lactation at Cincinnati Children’s Hospital Medical Center, noting that more research is necessary.
Necrotizing enterocolitis, or NEC, occurs in 10 to 15 percent of patients born before 36 weeks of gestation, and up to 40 percent of babies born at 24 or 25 weeks.
The mortality rate from the disease is nearly 30 percent.
The typical patient appears to be doing well for their first two weeks of life. Then, all of a sudden, they stop being able to digest food and their stomachs swell.
“It becomes clear that the child has developed a major problem in his or her tummy and an X-ray will usually confirm the diagnosis of necrotizing enterocolitis, in which the intestinal tissue is dying,” Dr. Hackam said. “We have no choice but to remove the dead parts of the intestine.”
Dr. Hackam still has quite a while before his research moves from mice to humans.
In his favor is that the compound of sodium nitrate that was added to mouse formula is already approved by the FDA for other uses.
Parents who are not able to provide breast milk to their babies who contract NEC often feel incredibly guilty, said Dr. Hackam, which is another reason why the possibility of adding sodium to breast milk is so promising.
He believes that concerns about nitrates causing cancer are not applicable in this case, because the levels added to formula would be so low.
“If there’s something that we can do to give the parents a little bit of hope,” he said, “we’ve done our job.”
The Block News Alliance consists of The Blade and the Pittsburgh Post-Gazette. Anya Sostek is a reporter for the Post-Gazette.
Contact Anya Sostek at: asostek@post-gazette.com or 412-263-1308.