A new set of symptoms has come to light in children who develop a somewhat mysterious inflammatory syndrome while infected with the coronavirus.
Early research suggests the coronavirus is mild in four out of five cases, with children in particular rarely developing serious complications.
Nevertheless, NHS doctors were told early in the outbreak to look out for signs of “multi-system inflammation”.
The warning came after intensive care units in London saw eight children with unusual symptoms, some of whom tested positive for the coronavirus.
Medics have likened the mysterious inflammation to atypical Kawasaki disease; a rare condition that usually affects children under five and causes blood vessels to become inflamed, leading to heart complications in around a quarter (25%) of patients.
Common symptoms were known to include a rash, swollen lymph nodes in the neck and dry, cracked lips.
After looking at 35 children who met the criteria for the mysterious inflammatory syndrome, medics from the New York University Grossman School of Medicine have reported how symptoms can also be “mucocutaneous”; defined as those that affect “body orifices”, like nostrils.
The youngsters were found to endure swollen eyes, flushed cheeks and even a “strawberry tongue”, to name a few symptoms.
Kawasaki disease is thought to come about when the immune system over-reacts to an infection. Left untreated, the heart complications can be fatal in 2% to 3% of patients.
Writing in the journal JAMA Dermatology, the New York medics noted “significant clinical overlap exists” between Kawasaki and the coronavirus-triggered inflammatory syndrome.
The latter, however, “has been characterised by more widespread systemic inflammation and higher rates of acute complications, including cardiogenic shock”; when the heart suddenly cannot pump enough blood to meet the body’s needs.
The mysterious inflammatory syndrome arising in some coronavirus-positive children has also been likened to toxic shock syndrome (TSS).
Often associated with tampon use, TSS is a medical emergency that can lead to fever, flu-like symptoms, nausea, vomiting and difficulty breathing.
Experts have warned these symptoms are a sign the body is overwhelmed as it tries to fight an infection.
Watch: Can you catch coronavirus twice?
To better understand the inflammatory syndrome, the New York medics analysed 35 children who were admitted to two hospitals between 1 April and 14 July, the “height” of the city’s pandemic.
Twenty five of the youngsters, who had an average age of three, met the criteria for the syndrome – aged 21 or under, with a fever, “laboratory evidence of inflammation” and severe illness requiring hospitalisation.
The syndrome was also defined as affecting “at least two organ systems”, with “no alternative plausible diagnosis”.
The remaining 10 participants, average age one, were “probable cases”.
Twenty nine of the children tested positive for the coronavirus.
Of the 35 patients, 29 (83%) endured “mucocutaneous changes”. The most common was bloodshot eyes, which affected 21 of the children.
Eighteen developed red palms, while 17 had “lip hyperemia”; defined as an increase in blood flow that may trigger redness or heat.
Strawberry tongue – when it is swollen, bumpy and bright red – affected eight of the patients.
Seven of the children endured red, swollen eyes, while six developed flushed cheeks.
These symptoms tended to arise two to three days after the onset of a fever, a tell-tale symptom of the coronavirus, and eased after five days.
Despite the symptoms’ “transient nature”, the medics hope other doctors will look out for the “important clues” of the inflammatory syndrome, with timely treatment being critical to a patient’s survival.
They stressed, however, these symptoms are not specific to the coronavirus-triggered inflammatory syndrome.
How common is the inflammatory syndrome?
The coronavirus-triggered inflammatory syndrome is said to be very rare.
A study published in the prestigious medical journal The Lancet details how 10 children developed a “rare inflammatory disorder” in the Bergamo province of Italy after the outbreak emerged in the north of the country.
Eight of these youngsters tested positive for coronavirus antibodies, with the Italian doctors wondering if the other two were false-negatives.
Only 19 children were diagnosed with a similar inflammatory disorder in Bergamo in the five years before the outbreak.
Although it is difficult to draw conclusions from such small numbers, the report suggests a 30-fold increase in incidences of the inflammatory syndrome.
While it may sound alarming, the vast majority of children are said to recover with hospital treatment, with experts repeatedly stressing there is no need to panic.
The Royal College of Paediatrics and Child Health previously advised parents to call 999 or take their child to A&E if they:
Become pale, mottled or abnormally cold to touch
Pause in their breathing, have an irregular breathing pattern or grunt
Have severe breathing difficulties, while becoming agitated or unresponsive
Go blue around the lips
Have a seizure
Become extremely distressed, confused, lethargic or unresponsive
Develop a rash that does not disappear with pressure, like when pressed under a glass
Have testicular pain, especially teenagers
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