Clinicians who see children with the novel coronavirus-related inflammatory syndrome similar to Kawasaki disease are being urged to seek advice from paediatric rheumatologists.

While likely to be rare in Australia, the newly-described Paediatric Inflammatory Multisystem Syndrome Temporally associated with SARS-COV-2 (PIMS-TS) is expected to increase  in regions with widespread community-based transmission of SARS-CoV-2, according to a new guidance statement released for Australian clinicians.

The advice developed by the Acute Inflammatory Vasculitis working group and the Paediatric Active Enhanced Disease Surveillance (PAEDS) network notes that there are increasing reports from the UK and Europe  of severely ill children and adolescents with fever and shock frequently associated with abdominal pain and rash associated with SARS-CoV-2 infection.

The timing of infection and clinical presentation suggests that PIMS-TS may be due to a delayed immune-mediated phenomenon triggered by the coronavirus.

There have been similar reports from the US, where the Centers for Disease Control and Prevention (CDC) has named this syndrome Multisystem Inflammatory Syndrome in Children associated with COVID-19 (MIS-C).

PIMS-TS shows similarities to Kawasaki disease Shock Syndrome (KSS), with children experiencing fever and shock, rash, and red hands and feet, and about 25% of cases having evidence of damage to the coronary arteries. However, PIMS-TS  tends to occur in older children (average age around 11 years) and seemingly more in African and Afro-Caribbean children.

According to the Australian guidance, released by the National Centre for Immunistion Research and Surveillance (NCIRS) in NSW, children with PIMS-TS also tend to have gastrointestinal symptoms (particularly abdominal pain) and a higher frequency of myocarditis and renal impairment.

“Initial reports show patients with PIMS-TS may have elevated inflammatory markers, including ESR, CRP and ferritin, along with abnormal coagulation studies,” it notes.

“However, other laboratory parameters appear more specific for PIMS-TS, including lymphopaenia and thrombocytopaenia on full blood count, and hyponatraemia. An elevated troponin may occur.”

It is recommended that children with suspected PIMS-TS be investigated and treated with expert advice sought as needed from specialist services such as paediatric infectious diseases, paediatric rheumatology, paediatric cardiology and paediatric immunology.

Currently, the evidence suggests that appropriate supportive management should be started with specific measures for hypotension or shock instituted urgently if required. Children with PIMS-TS have also been managed with intravenous immunoglobulin (IVIG).

“The outcome of PIMS-TS is generally good. While the majority of children reported to date have recovered, five deaths have been reported to date,” the advice for clinicians says.

And based on the eight cases reported in a UK region with ten times the population of Australia, it suggests that PIMS-TS will be uncommon in Australia. Any increase in Kawasaki Disease-like syndrome in Australia is likely to be detected by the  national registry that currently reports stable rates of around 400 cases of typical KD per year in Australia.

“PIMS-TS appears to be a rare, but clinically significant, complication of SARS-CoV-2 infection. The overall risk for any severe COVID-19 outcomes in children in the Australian context remains extremely low,” the advice concludes.