Most children are asymptomatic or suffer only mild symptoms from Covid-19. Less than 1.5 per cent of all admissions to hospital with Covid-19 are of people under 20, and even fewer require admission to an intensive care unit. However, since April, coinciding with the spread of the virus, a small number of children have become unwell with symptoms and signs of inflammation.
Although doctors do not yet fully understand the relationship between Covid-19 and this new condition, or even whether there is one, they believe the syndrome, which has become known as PIMS-TS, could be linked to the virus.
WHAT IS PIMS-TS?
The newly discovered condition is a significant systemic inflammatory response, known as Paediatric Inflammatory Multisystem Syndrome Temporally associated with SARS-CoV-2 (PIMS-TS).
PIMS-TS seems to be linked to Covid-19 because most of the children affected either have the virus or test positive for antibodies indicating that they have been infected before.
Dr Sanjay Patel, infectious diseases lead at the Royal College of Paediatrics and Child Health (RCPCH), explains, ‘We saw a very steep increase in Covid-19 in the week after lockdown. There was then a delay of three to five weeks between the start of these Covid cases and the start of PIMS, so PIMS is likely to be linked to and driven by COVID.’
While PIMS-TS is very rare and most children with the condition will not be seriously affected, in a very few cases it has been serious and even life-threatening.
WHAT ARE THE SYMPTOMS?
PIMS-TS has no diagnostic test, and patients can show a wide range of symptoms and be affected very differently. Some children may have a rash. Some may have abdominal symptoms such as stomach ache, diarrhoea or vomiting. All the children diagnosed with PIMS-TS so far have had a high temperature for more than three days.
In severe cases of PIMS-TS, where children have serious inflammation throughout their body, the inflammation could spread to blood vessels (vasculitis), particularly those around the heart, which, if left untreated, could cause tissue damage, organ failure or even death.
Seriously affected children will have symptoms which look similar to other life-threatening conditions such as sepsis or meningitis.
WHAT IS THE TREATMENT?
Doctors treat the symptoms of PIMS-TS individually, often using a combination of treatments such as antibiotics, steroids, aspirin and immunoglobulin.
Dr Patel explains, ‘Doctors and nurses are well aware of this new condition and reassuringly we have been highly effective at treating it in the majority of cases. We are also running lots of research trials at the moment to further understand the effects of different treatments.’
HOW MANY CHILDREN HAVE BEEN AFFECTED?
Current estimates are that between 90 and 120 children may have been seriously affected by PIMS-TS and admitted to an intensive care unit in the UK. Almost all these children have since recovered, with one death reported. However, it is difficult to be sure of numbers.
The RCPCH has sent a survey to 2,500 paediatricians in an attempt to gain details of every case seen in hospitals since the beginning of March, and expects the results to show around 200 cases in England alone. However, the organisation acknowledges the survey is likely to pick up some cases which will later turn out to be a different illness, and potentially miss a much larger number of children who have had the condition mildly and recovered without ever seeing a doctor.
WHAT SHOULD EARLY YEARS PRACTITIONERS LOOK OUT FOR?
Practitioners should continue to be as vigilant as ever, says Dr Patel. ‘All these cases have been diagnosed without people knowing anything about PIMS. Everyone knows the things that show a child is unwell and needs treatment, like a temperature of 38?C or higher, cold hands and feet or sleepiness, and this is no different. Children present with classic signs.’
He recommends referring to the RCPCH’s traffic light system (https://what0-18.nhs.uk/national/coronavirus). However, Dr Patel also reassures practitioners that they should not be unduly worried, adding, ‘Covid-19 appears to be rare in children, and the likelihood of PIMS-TS is extremely low.
‘There has been a lot of hype in the media, as when something involves children, people get panicky. It can be hard to be rational and objective. But these are not large numbers, and the children affected tend to be older, with an average age of nine in the UK and seven in France, for example. It is really important to get that perspective.’
HOW IS PIMS-TS RELATED TO KAWASAKI DISEASE?
Some of the symptoms of PIMS-TS can overlap with other rare conditions, such as Kawasaki Disease, which has been well-documented in media reports during the pandemic.
Kawasaki Disease is an acute illness usually seen in children under five. It is a seasonal inflammatory disorder peaking in the winter and spring and affecting almost every system in the body.
The defining characteristic of the disease is a distinctively persistent high fever. Other symptoms can include a rash, cracked lips and sore mouth, bloodshot eyes, and swollen glands in the neck, often just on one side.
Like PIMS-TS, complications from Kawasaki can cause damage to the heart. However, Rachael McCormack, founder of Societi, the UK Kawasaki Disease Foundation, calls the ‘mishandling of information’ in comparisons between PIMS-TS and Kawasaki Disease ‘worrying’.
‘I’m frustrated, like many in our community, that it has been casually described as “Kawasaki-like” – which has done nothing but create more confusion.
‘Kawasaki Disease is often misdiagnosed at first because it has symptoms common with many illnesses – so the phrase “Kawasaki-like” is just not helpful. It might as well have been “measles-like” or “sepsis-like”. These are equally uninformative phrases.’
Any one of many infections may trigger Kawasaki Disease, but no infection has ever been proven to be the sole trigger. In the majority of cases, Kawasaki Disease occurs without the infectious cause ever being identified.
While Dr Patel acknowledges it is ‘not unreasonable’ to think Covid-19 could trigger Kawasaki Disease in some cases, he warns this would be the case in only a ‘minuscule proportion’ of sufferers.
‘The numbers are not high and it is not a clear trigger, so it is very important not to get a message out there that Covid triggers Kawasaki Disease,’ he says.
During the pandemic, cases of Kawasaki Disease have actually been fewer than would normally be expected at this time of year, and half the sufferers tested negative for Covid-19.
Ms McCormack adds, ‘It is very important that doctors quickly learn more about PIMS-TS and, already, many research studies are under way to gather evidence, build up and share knowledge.
‘Perhaps in learning more about PIMS-TS we will learn more about Kawasaki Disease too.’