Marcia Frellick

April 07, 2023

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Researchers have found for the first time that COVID infection has crossed the placenta and caused brain damage in two newborns, according to a study published online today in Pediatrics.

One of the infants died at 13 months and the other remained in hospice care at time of manuscript submission.

Lead author Merline Benny, MD, with the division of neonatology, department of pediatrics at University of Miami, and colleagues briefed reporters today ahead of the release.

"This is a first," said senior author Shahnaz Duara, MD, medical director of the Neonatal Intensive Care Unit at Holtz Children's Hospital, Miami, explaining it is the first study to confirm cross-placental SARS-CoV-2 transmission leading to brain injury in a newborn.

Both infants negative for the virus at birth

The two infants were admitted in the early days of the pandemic in the Delta wave to the neonatal ICU at Holtz Children's Hospital at University of Miami/Jackson Memorial Medical Center.

Both infants tested negative for the virus at birth, but had significantly elevated SARS-CoV-2 antibodies in their blood, indicating that either antibodies crossed the placenta, or the virus crossed and the immune response was the baby's.

Dr. Benny explained that the researchers have seen, to this point, more than 700 mother/infant pairs in whom the mother tested positive for COVID in Jackson hospital.

Most who tested positive for COVID were asymptomatic and most of the mothers and infants left the hospital without complications.

"However, (these) two babies had a very unusual clinical picture," Dr. Benny said.

Those infants were born to mothers who became COVID positive in the second trimester and delivered a few weeks later.

Seizures started on day 1 of life

The babies began to seize from the first day of life. They had profound low tone (hypotonia) in their clinical exam, Dr. Benny explained.

"We had absolutely no good explanation for the early seizures and the degree of brain injury we saw," Dr. Duara said.

Dr. Benny said that as their bodies grew, they had very small head circumference. Unlike some babies born with the Zika virus, these babies were not microcephalic at birth. Brain imaging on the two babies indicated significant brain atrophy, and neurodevelopment exams showed significant delay.

Discussions began with the center's multidisciplinary team including neurologists, pathologists, neuroradiologists, and obstetricians who cared for both the mothers and the babies.

The experts examined the placentas and found some characteristic COVID changes and presence of the COVID virus. This was accompanied by increased markers for inflammation and a severe reduction in a hormone critical for placental health and brain development.

Examining the infant's autopsy findings further raised suspicions of maternal transmission, something that had not been documented before.

Coauthor Ali G. Saad, MD, pediatric and perinatal pathology director at Miami, said, "I have seen literally thousands of brains in autopsies over the last 14 years, and this was the most dramatic case of leukoencephalopathy or loss of white matter in a patient with no significant reason. That's what triggered the investigation."

Mothers had very different presentations

Coauthor Michael J. Paidas, MD, with the department of obstetrics, gynecology, and reproductive sciences at Miami, pointed out that the circumstances of the two mothers, who were in their 20s, were very different.

One mother delivered at 32 weeks and had a very severe COVID presentation and spent a month in the intensive care unit. The team decided to deliver the child to save the mother, Dr. Paidas said.

In contrast, the other mother had asymptomatic COVID infection in the second trimester and delivered at full term.

He said one of the early suspicions in the babies' presentations was hypoxic ischemic encephalopathy. "But it wasn't lack of blood flow to the placenta that caused this," he said. "As best we can tell, it was the viral infection."

Instances are rare

The researchers emphasized that these instances are rare and have not been seen before or since the period of this study to their knowledge.

Dr. Duara said, "This is something we want to alert the medical community to more than the general public. We do not want the lay public to be panicked. We're trying to understand what made these two pregnancies different, so we can direct research towards protecting vulnerable babies."

Previous data have indicated a relatively benign status in infants who test negative for the COVID virus after birth. Dr. Benny added that COVID vaccination has been found safe in pregnancy and both vaccination and breastfeeding can help passage of antibodies to the infant and help protect the baby. Because these cases happened in the early days of the pandemic, no vaccines were available.

Dr. Paidas received funding from BioIncept to study hypoxic-ischemic encephalopathy with Preimplantation Factor, is a scientific advisory board member, and has stock options. Dr. Paidas and coauthor Dr. Jayakumar are coinventors of SPIKENET, University of Miami, patent pending 2023. The other authors have no conflicts of interest to disclose.

This article originally appeared on MDedge.com, part of the Medscape Professional Network.

Source: https://www.medscape.com/viewarticle/990554?src=FYE#vp_1