India
Some symptoms of MIS-C overlap with those of Kawasaki disease
“ We don ’ t really know for sure what the prevalence is as each hospital has its own numbers , and the data are not centralised .” problems , along with a current or recent COVID-19 infection .
When MIS-C was first reported in the research literature , it was suggested that it affected one in every thousand children infected with COVID-19 . Since reporting on the condition has been rudimentary , however , there are no definitive numbers , although in India , reported figures suggest 2-3 cases per thousand infected children .
What makes it harder to gauge prevalence is that some patients who have been exposed to parents with COVID-19 go on to contract MIS-C even though their own swab test turns out to be negative , according to Dr Marhisham Che Mood , a senior consultant paediatric cardiologist at IJN , Malaysia ’ s National Heart Institute .
“ We don ’ t really know for sure what the prevalence is as each hospital has its own numbers , and the data are not centralised ,” he said . “ However , I do believe we will get more accurate data in the near future . It ’ s probably easier to catch the occurrence of MIS-C amongst positive COVID-19 children .”
One interesting note is that , in spite of its similarities with Kawasaki disease , the new syndrome has a much lower prevalence in countries that would typically have high numbers of Kawasaki .
“ That ’ s one of the more intriguing questions about this syndrome . Korea is a good example as Koreans have a high genetic predisposition for Kawasaki disease , but there has not been a spike in Kawasaki disease or a spike in this syndrome during the pandemic ,” said Dr Stock .
Most often , a child will be infected with COVID-19 , and 4-6 weeks later , they will develop the new syndrome . What this tells researchers is that it ’ s probably a consequence of the immune response that develops due to the virus , rather than the virus itself .
The prevailing theory is that a small fraction of these children will develop auto-antibodies to the endothelial ( outer ) layer of blood vessels . This then causes inflammation within the different organs fed by these vessels .
“ Generally , the treatments offered are the standard supportive treatments that we give to patients who present with toxic shock syndrome due to infection or Kawasaki disease ,” said Dr Marhisham .
The treatment may include breathing assistance through ventilator support , inotropes to support the heart by changing the force of the contractions , and medicines such as steroids to reduce or stop ongoing inflammation .
Since MIS-C is a newly described illness , more observation is needed before it ’ s possible to know if children with the syndrome are at greater risk of other cardiovascular problems during their lifetimes . However , its similarities with Kawasaki disease might provide a clue .
Kawasaki researchers were not surprised to find that an illness linked to it developed after the onset of the pandemic . It had been known for a long time that Kawasaki is most likely triggered by a respiratory viral infection , and the prevailing view was that many types of viruses would do that .
Indeed , other family members of the coronavirus family have been identified as triggers for Kawasaki disease .
The longer-term complications of Kawasaki disease are that the coronary arteries become blocked , and this can occur weeks , months , or even years after the disease first appears , leading to inflammation within the heart . This brings about a chain of events that causes the coronary arteries to become increasingly narrower and eventually blocked .
“ This may also be the case for those with MIS-C . However , long term follow-up is essential to understand the new syndrome better , especially by looking at different cohorts of risk groups in children ,” Dr Marhisham added .
As a specialist in Kawasaki disease , Dr Stock hopes his research into why the coronary arteries narrow and his work developing therapies to stop that progression will also lead to better treatment for
42 JUNE 2021 GlobalHealthAsiaPacific . com