Cases of unexplained hepatitis in children keep Montreal doctors on the lookout

No cases have been reported in Quebec, but the World Health Organization says about 200 instances of acute liver disease “of unknown origin” have been found in children across a dozen countries.

Jesse Feith 4 minute read May 5, 2022

Though they say it’s too early for people to be alarmed, Montreal pediatricians are keeping an eye out for any cases of a severe and unexplained form of hepatitis affecting children around the world.

According to the World Health Organization, about 200 cases of acute liver disease “of unknown origin” have been found in children across a dozen countries.

The Public Health Agency of Canada says it’s investigating “potential cases” in Canada to know whether they’re linked to those found in the United Kingdom and the United States.

In interviews this week, doctors with Montreal’s two main children’s hospitals said they don’t believe parents should be panicked by the outbreak just yet.

But they stressed how important it is for physicians to look for cases and report them to public health authorities to better understand what’s happening.

“Is it concerning? Yes, because we haven’t really pinned down what the cause is, and that’s always a concern,” said Dr. Jesse Papenburg, a pediatric infectious disease specialist at the Montreal Children’s Hospital.

“But should families be concerned for their children at this point? I would say no.”

The WHO first reported on the outbreak in mid-April. Its latest tally has put the number of cases at just over 220 worldwide, with the bulk of them being reported in the United Kingdom.

Hepatitis is an inflammation of the liver that can be caused by different medical conditions or intoxication by drugs or other substances. It’s most commonly caused by a virus.

The cases in question have been described as mysterious because the viruses that usually cause acute hepatitis haven’t been detected in any of them. Roughly 10 per cent of the children affected have required a liver transplant and one death has been reported.

Given the pandemic, a connection to a previous COVID-19 infection is being probed, but not all affected children tested positive for the SARS-CoV-2 virus.

The WHO says a link to the COVID-19 vaccine has been ruled out, as most of the children had not received the vaccine.

Contacted about the outbreak, Quebec’s Health Ministry said it has yet to be notified of any cases in the province.

“Instructions for reporting cases of severe acute hepatitis of unknown origin will soon be widely distributed to the various clinicians,” a spokesperson wrote in an email response, “allowing these cases to be documented.”

One of the causes being investigated in the outbreak is a possible link to an adenovirus infection. A common virus that usually causes respiratory symptoms or gastrointestinal issues, adenovirus was detected in at least 74 of the cases to date, the WHO says.

Dr. Fernando Alvarez, a hepatologist and the director of the liver transplant program at Montreal’s Ste-Justine Hospital, said another theory worth pursuing is whether the outbreak is somehow related to the lockdown measures seen throughout the COVID-19 pandemic.

“For parts of two years, schools were closed and children were kept home. And during that time we’ve seen a decrease in the circulation of many viruses, including adenovirus,” Alvarez explained.

“That means children, mainly young children, were not immunized against those viruses,” he continued. “One possible hypothesis is that the recirculation of adenoviruses is now attacking children that were not prepared (to face) these kinds of infections.”

Alvarez said acute hepatitis is not unheard of in children, but the numbers coming out of the United Kingdom (114 as of the latest update) are “surprisingly higher” than usual.

As a comparison, he said, Quebec usually sees one to three cases of unexplained hepatitis in children per year. And about one child requires a liver transplant due to hepatitis every two to three years in Quebec, he added.

Alvarez said it will be crucial moving forward to detect any cases locally and report them to federal authorities to establish the incidence in Canada.

Papenburg agreed. “We need to keep an eye out for these cases and systematically investigate them, in terms of all the possible etiologies,” he said. “Because so far we have some suspicions, but it’s not the usual suspects that are causing this.”

Papenburg also said parents should know what to look out for in their children.

Early symptoms of hepatitis can include lethargy, loss of appetite and abdominal pains. But it should be considered a red flag, he added, when those are accompanied by jaundice, dark urine or pale stools.

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