Thread by @apsmunro

Paediatric hepatitis twitter is a little wild at the moment

As a result, there is a lot of stuff circulating which is totally incorrect

Whilst there's much we don't know, there is some stuff we KNOW is not true

A short thread to bust some myths 💥

1/ 🧵

The important take-away is that these cases COULD be linked to #COVID19 and this must be investigated, but there is little certainty over *any* of the current hypotheses

Lots of people however seem certain it is related to covid, and therefore false links have been made

2/

First, a recent paper from Japan purports to show an epidemiological link between Omicron and cases of paediatric hepatitis

It actually just shows big countries have more people, and more people means more cases of #COVID19 and hepatitis

See thread

3/

https://twitter.com/apsmunro/status/1525164612735344640?s=20&t=wr6WS5sgKbv3Lxy_S6PGJw

People are also sharing cases of #COVID19 causing hepatitis in other children as if this is proof

These are categorically NOT what is happening in the current outbreak, as acute covid hepatitis is easy to diagnose, and most cases are not covid +ve

4/
journals.lww.com/jpgn/Abstract/…

A case of post-covid autoimmune hepatitis is being shared as if this is an explanation

This case was diagnosed by anti-lkm antibodies, a test for autoimmune hepatitis which should be done on all cases, and if +ve would EXCLUDE them from the outbreak

5/
ncbi.nlm.nih.gov/pmc/articles/P…

This is VERY important - the case definition means that causes such as autoimmune hepatitis and acute covid hepatitis would explicitly be excluded from this outbreak analysis

It is puzzling precisely because these causes are being investigated and have not been found

6/

Now @BrodinPetter has proposed a very elegant hypothesis in Adenovirus triggering activation of intestinal reservoir of #SARSCoV2 and subsequent superantigen stimulated liver disease

This has no supporting evidence *yet*, but needs investigating

7/

https://twitter.com/BrodinPetter/status/1525246188404060161?s=20&t=wr6WS5sgKbv3Lxy_S6PGJw

It's worth noting the hypothesis leans on the hypothesis of a similar mechanism behind MIS-C

This is based on work showing S antigen in blood of MIS-C patients in a study from Massachusetts

However...

8/
jci.org/articles/view/…

A separate study from Boston children's hospital with a larger sample size did not replicate this finding, despite antigen being present in blood of children with acute #COVID19

This doesn't rule it out, but shows the case is far from cut and dry

9/
pubmed.ncbi.nlm.nih.gov/35213684/

The reason these cases are noteworthy is there is *no obvious cause*

As described elsewhere, Adenovirus 41 appears so frequently to raise suspicion, but wouldn't normally cause this kind of disease

Everything is on the table, but needs investigating carefully, without bias

10/

I won't go into all the potential hypotheses here as it's not the point, and there are plenty of good documents from @UKHSA, @ECDC_EU and @CDCgov

My advice would be: anyone who suggests the cause is obvious is not a trustworthy source of information on this topic

11/end