SINGAPORE: A retrospective investigation by the Ministry of Health (MOH) revealed another two cases of acute hepatitis of unknown cause - a three-year-old and an eight-year-old who developed the illness in October and November 2021 respectively.
Laboratory testing determined that these two cases are negative for the common hepatitis viruses.
Both children did not have a history of COVID-19 prior to their acute hepatitis, and continue to be under regular follow-up, said MOH.
Additionally, in an update of the case of a 10-month-old infant who was found to have acute hepatitis last month, MOH said that baby boy has been discharged and is currently well.
The cause of the hepatitis - also known as liver inflammation - "remains indeterminate".
On Apr 25, the baby was admitted for further investigations at KK Women’s and Children’s Hospital Emergency Department. The health ministry was notified of case four days later.
Following a World Health Organization (WHO) alert of cases of acute hepatitis of unknown cause in young children, MOH took measures to determine if the boy's case was similar to those seen across the world.
All hospitals with paediatric services were asked to review their patient records for those who have a similar presentation to the cases reported by WHO, MOH said.
This was when the three-year old and eight-year old were identified.
"Hepatitis in young children is not uncommon and it is not unusual for the cause of some hepatitis cases in children to remain unknown," MOH said.
It added that no unusual increase or pattern has been observed in the number of children with hepatitis of unknown cause.
While the cause of hepatitis in all three cases in Singapore has not been identified, it does not mean that they are linked to the global outbreak, said MOH.
"We continue to monitor the situation closely and have informed all medical practitioners to be vigilant to young children presenting with signs and symptoms of hepatitis for which a cause cannot be identified."
The first cases of acute hepatitis with unknown cause among children were identified at an Alabama hospital in October 2021, when five patients were admitted with liver damage.
Since then cases were reported in several countries including Japan, Indonesia, the United Kingdom, Spain and France.
Many of the affected children are aged 10 and under, and the youngest was one month old.
Common symptoms include abdominal pain, diarrhoea and vomiting, followed by jaundice, which is marked by the skin or the whites of the eyes turning yellow.
The affected children may also have fatigue, loss of appetite, dark urine, light-coloured stools and joint pain.