It looks like they are caused by #SARSCoV2 after all, but people have been looking with the wrong test.
It seems pretty conclusive now that #COVID19 cases in children are being missed.
A short thread...
![](https://pbs.twimg.com/media/EfcsyOUU8AEOFw1.jpg)
Doctors in Italy noticed "an epidemic of acroischemic lesions of some toes and fingers in asymptomatic children and adolescents", at the height of the epidemic but weren’t able to do testing.
This suggested that the phenomenon might be a way to spot some of the children who might be asymptomatic carriers.
These children were negative by RT-PCR and serology in Spain, and negative by RT-PCR in Belgium.
Biopsies were negative by RT-PCR in Belgium, too.
In this case series of 7 children aged 11-17 years, all who were tested for #SARSCoV2 by RT-PCR (n=6) were negative. But monoclonal antibody tests of biopsies were positive for all 7 children.
onlinelibrary.wiley.com/doi/full/10.11…
She tested negative for #SARSCoV2 by RT-PCR and serology (the latter performed 6 weeks later), but biopsy of the lesions was positive (by RT-PCR).
thelancet.com/journals/lance…
First, #CovidToes probably is a symptom of #COVID19 in most cases. We just haven’t been doing the right tests.
Second, some people (particularly children) do not seem to test positive for #COVID19 and may not produce antibodies.
There’s a lot more to the immune system than antibodies, but it does raise questions about whether some people develop sufficient immunity after infection.