Campus Scientists Help With Solving Mysterious Liver Disease in Children

What can you tell us about Colorado’s 13 cases?

It’s really important to understand that these are not confirmed cases. We submit to the CDPHE (Colorado Department of Public Health and Environment) and CDC any patients dating back to October 2021 who meet certain criteria: under age 10 with severe hepatis of unknown etiology. As of May 19, there were 13 such cases under investigation.

Is the public health concern then centered on the fact that the cases have no known cause?

Many times with hepatitis, children recover, and we never identify the specific cause of the liver inflammation. Additionally, a certain percentage of children who have severe hepatitis leading to acute liver failure have no identified cause. So indeterminant hepatitis is not a new thing.

I think what is attracting attention is that there appears to be an increased cluster of cases occurring at this time around the world. Additionally, some of the children with severe hepatitis are testing positive for adenovirus, a virus that commonly causes respiratory and gastrointestinal symptoms in children, but rarely causes severe liver inflammation or acute liver failure in healthy children. So people are worried that there may be a novel infection or a more pathogenic infection currently circulating.

Children’s Hospital Colorado and other liver centers across the country are contributing cases and studying these cases so that we can understand if there is truly an increase in the number of pediatric hepatitis cases and, if so, what might be the cause.

Media reports suggest COVID-19 vaccines have been ruled out as a cause. Can you share why?

I don’t think that anything has been ruled in or out at this point in time. As a scientific community, we are really just starting to gather information so that we can answer some of these questions. But it is important to remember that the COVID vaccine is not approved for children under the age of 5, so many of the reported cases of severe hepatitis occurred in children who would not yet have been vaccinated.

With monkeypox also in the headlines along with this mystery hepatitis, is it possible that these disease outbreaks could be related to two-plus years of isolation from exposure to pathogens because of the pandemic? And what are the chief suspected causes?

If we find that there is an increased amount of pediatric hepatitis occurring across the world, there are various hypotheses that would be worth investigating, including: 1) Children have a different susceptibility or response to infections after not being exposed to as many infections during the COVID pandemic; 2) There might be a changed susceptibility or response to infections in those children who had prior infection with COVID-19; 3) There is a larger than normal wave of a specific infection (such as adenovirus) occurring or a novel or more pathogenic infection currently circulating.

In addition to infections, people are also investigating potential drug, toxin or environmental exposures.

What other advice do you have for parents?

The best things for parents to do is to make sure their children are up to date on vaccines. The hepatitis A and hepatitis B vaccines are two examples that keep the liver healthy. Also, handwashing, masking and/or distancing when someone is coughing or sneezing can help prevent person-to-person transmission. If parents are concerned that their child has hepatitis symptoms (see list above), they should call their pediatrician or bring their child to the emergency department.

I also would emphasize that severe hepatitis resulting in liver failure is very rare in children. Before all this started, of the 500 to 600 pediatric liver transplants performed across the United States each year, only 10 to 15 percent of them (50 to 90 transplants a year) were for acute liver failure. The majority of children who have acute hepatitis will recover without transplantation.