Unexplained Acute Hepatitis in Kids: Is It Linked to COVID-19?

Investigators suspect the virus causing unexplained acute hepatitis in young children could be linked to COVID.

Acute hepatitis in children: 

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Researchers have been jumping through hoops trying to find the answers to a recent spurt in unexplained acute hepatitis in young children around the world.

Major health authorities including the World Health Organisation (WHO), the US Centre for Disease Control and Preventing (CDC) and the UK Health Security agency have issued alerts as cases continue to increases in countries across the world.

None of the known hepatitis viruses (A - E) have been detected in these patients, and researchers are yet to figure out what exactly is causing this phenomenon.

A new study suggests that the disease may be linked to COVID-19. Here's what to know.

Acute Hepatitis in Young Kids: What Do We Know?

Acute Hepatitis is caused when there is an inflammation in the liver resulting in elevated levels of liver enzymes in the blood. The disease is caused mainly due to one of the hepatitis viruses, or as a result of some autoimmune conditions.

Common symptoms to watch out for are,

• Abdominal pain

• Diarrhoea and vomiting.

• Jaundice

• Fatigue

• Loss of appetite

• Joint pain

• Dark urine

Before we look at the latest study, here's a quick run through of what we know about the unexplained rise in acute hepatitis in kids.

The first case was reported in October 2021 in Alabama, USA. What was thought to be an isolated incident quickly became a number of similar cases mushrooming in the US, UK, and other countries in Europe.

Since then cases have also been reported in countries in Asia including Japan and Indonesia.

So far, upwards of 200 cases have been reported in parts of Europe, Asia, and the Americas. According to the WHO, around 10 percent of these patients ended up needing liver transplant.

While the usual suspects of Hepatitis were not found in these kids, curiously enough, around two thirds of them tested positive for adenovirus 41F—the kind responsible for common cold and flu like symptoms.

This adenovirus is not typically known to affect the liver, so it might be too early to draw causation from this correlation.

In the meantime, researchers are also exploring other explanations and possible causes.

What the Study Has Found

Mounting evidence suggests that COVID is a multisystem infection, and can impact any organ in the short and long term.

So, could COVID also cause hepatitis? Yes, say the study researchers.

• The study comprised of 796,369 children between the ages of 1-10 years.

• 245,675 of them had contracted COVID-19 between March 11, 2020 - March 11, 2022

• 550,694 had contracted non-COVID other respiratory infection (ORI) during the same timeframe.

Results: Compared to children who had ORI, children with COVID-19 were found to be at a significantly higher risk for elevated alanine transaminase (ALT), and total bilirubin—two indicators of liver damage.

The researchers, however, have not been able to conclusively link these findings to the emerging cases of acute hepatitis.

To make matters more confusing, most of the kids with acute hepatitis did not test positive for COVID.

COVID in children as young as these (under 10 years) is rare, but experts aren't completely ruling out the possibility of some of these kids having had asymptomatic or very mild COVID that may have gone unnoticed.

Another similar study, published in The Lancet Gastroenterology & Hepatology, found that around 18 percent of the patients in the UK did in fact test positive for COVID.

In Israel, according to the same study, Eleven of twelve patients were reported to have had COVID-19 in recent months.

The study researchers think viral reservoir formation post COVID could be one explanation for these cases of acute hepatitis.

"SARS-CoV-2 viral persistence in the gastrointestinal tract can lead to repeated release of viral proteins across the intestinal epithelium, giving rise to immune activation."

Lancet study authors

Repeated immune activation has previously been linked to multisystem inflammatory syndrome in children, which can also lead to liver failure in some cases.

More research, however, is needed to establish this theory more conclusively.