There has been a “startling increase” in the number of fetal situs inversus at two Chinese obstetric centers after the country’s zero-COVID policies were lifted, the researchers reported.
From January to July this year, the occurrence of situs inversus — a rare congenital disorder in which the visceral organs are inverted from their overall position — was more than 4 times higher than the average annual occurrence from 2014 to 2022 at both centers, which were not in the same region, Shan Bian reported. PhD, from Tongji University in Shanghai, and colleagues.
In the first seven months of 2023, a total of 56 cases of situs inversus fetal (52 cases of situs inversus globalis and four cases of partial situs inversus were known) in the first seven months of 2023, with a peak incidence in April, they noted correspondently in the New England Journal. of Medicine.
Cases were diagnosed by regimen ultrasound at a gestational age of approximately 20 to 24 weeks, with no adjustments in diagnostic protocol or physician training.
“Although vertical transmission of SARS-CoV-2 is debated, fetal infection in the early stages of gestation can hypothetically simply be visceral lateralization; alternatively, maternal inflammatory responses mediated by SARS-CoV-2 may indirectly serve as a left-right organizer and alter visceral lateralization. Bian and his co-authors wrote.
“Right now, we are investigating the conceivable arrangement between SARS-CoV-2 infection in the first few weeks of gestation and situs inversus through a multicenter cohort study,” Bian told MedPage Today in an email. “In this research, we will take into account every conceivable threat point, such as SARS-CoV-2 infection, maternal environmental exposure, and genetic evaluation of the fetus. “
“In addition, the conclusion would be more informative if we could have more patients and institutions more engaged, adding hospitals from other countries,” he said. “International collaboration is welcome in our long-term study. “
A backlog of COVID infections after the lifting of zero-COVID policies in China began in early December 2022, peaked around Dec. 20 and ended in early February 2023, Bian and co-authors noted. It is estimated that 82% of the population has been affected.
“While those early observations are, of course, interesting, it’s vital to note that this is just an observation, not a company agreement or a causal link,” said Katherine Kohari, MD, maternal-fetal medicine specialist at Yale Medicine in New Haven. , Connecticut, told MedPage Today in an email.
“There are possibly other reasons for the increase in cases seen in the population,” he said. “In addition, there has not been an increase in in situ inversus rates in other periods when there were likely peak COVID-19 rates. We also don’t know if patients whose fetuses were diagnosed with situs inversus also had COVID-19 infections during pregnancy. “
“Therefore, the situation deserves to be explored in more detail in a peer-reviewed publication of studies, with more detail related to exposures during pregnancy in each of the diagnosed cases compared to fitness controls,” he added. “Even then, causality would be complicated to prove. “
Bethany Stetson, MD, a maternal-fetal medicine specialist at Northwestern University Feinberg School of Medicine in Chicago, echoed that sentiment, noting, “I think we’re at a very early stage. “
At the same time, a birth defect is accumulating, “which warrants further investigation,” she told MedPage Today, adding that “it never hurts to report it to other centers. “
Stetson also said it’s a significant leap to say this express is directly similar to the lifting of zero-COVID policies.
Both Stetson and Kohari pointed to well-known viral links to a variety of fetal anomalies, but not to situs inversus, though they said the latter was not out of the question.
“I’m aware of any viruses related to the progression of situs inversus in the fetus,” Kohari said. “Other viral infections are known to cause abnormalities in fetal progression, so it is credible that the COVID-19 virus may also cause fetal abnormalities. “, however, there is still [important research] to be done to further explore this relationship. “
As for the prognosis, Stetson said many other people with situs inversus do have an overall life expectancy. However, there is still the fear and need to look for other symptoms that may also be present, such as congenital heart defects, she added.
Kohari noted that “in general, if there is a true mirror image, then most people with that diagnosis do very well. Sometimes this diagnosis is made incidentally. However, there are variants of this arrangement that are possibly more related to functional and anatomical aspects. “problems. “
The study authors also noted that no conclusions can be drawn about causation. At the same time, they said their observations “suggest a possible dating between SARS-CoV-2 infection and fetal situs inversus that warrants further study. “
“Further analysis is needed to determine that genetic abnormalities in genes similar to ciliary dyskinesia number one that may not have been detected on prenatal genetic testing did not contribute to the occurrence of those cases and to assess the potential contribution of environmental factors. “wrote. ” It is notable that situs inversus diagnoses have remained incredibly rare despite the increase in their incidence in our centers following the rise of SARS-CoV-2. “
Jennifer Henderson joined MedPage Today as a corporate and research writer in January 2021. He has covered healthcare, life sciences, and New York City law, among other areas.
Studies supported through grants from the National Key R Program
The authors reported any conflicts of interest.
Neither Kohari nor Stetson reported conflicts of interest.