Hepatitis (Acute) – Unknown Origin in Children | Public Health Ontario - ISS-G20 Laboratorium Repository

Testing Indications

There have been reports since January 2022 of increased numbers of acute hepatitis cases without known aetiology in children from the United Kingdom, Europe, Israel and the United States. Cases date back to October 2021. Hepatitis A, B, C, D and E viruses were ruled out in all of the cases and other infectious aetiologies are being investigated. There is no known association with travel. WHO issued the following release on April 23, 2022: https://www.who.int/emergencies/disease-outbreak-news/item/multi-country-acute-severe-hepatitis-of-unknown-origin-in-children

The clinical syndrome in currently identified cases is of severe acute hepatitis with markedly elevated transaminases level of >500 U/L, often with jaundice and sometimes preceded by gastrointestinal symptoms, in children up to 16 years of age. Some cases require transfer to pediatric hospitals for specialized care, including a small number that have undergone liver transplantation. As of April 25, 2022, one death has been reported in association with these incidents. Underlying causes remain unknown, but adenovirus has been identified in some cases.

Clinicians should be alert to this emerging situation, and be vigilant to infants and children presenting with signs and symptoms potentially attributable to hepatitis that may require liver function testing. These include new onset of the following:

• Jaundice (yellow skin and/or eyes)
• Dark urine and/or pale stools

Considering the appropriate clinical context, other symptoms that may be suggestive of hepatitis include:

• Pruritus
• arthralgia / myalgia
• lethargy
• loss of appetite
• nausea, vomiting or abdominal pain
• fever

PHO’s laboratory is providing testing to support the investigation of cases of hepatitis in children. Clinicians caring for children presenting with sign and symptoms that may indicate hepatitis as listed above may request the expanded testing panels described here to rule in/out infectious aetiologies.

Entire content available on: https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Hepatitis-of-Unknown-Origin-in-Children