Thread by @allanmjoseph

The "mysterious pediatric coronavirus illness" resembling Kawasaki Disease (KD) and toxic shock syndrome (TSS) has been in the news recently. From a current pediatrics resident and soon-to-be #PedsICU fellow, let's talk a little bit about it. (Thread).

nytimes.com/2020/05/09/hea…

First, what's KD? It's an inflammatory disease that can cause problems with the coronary arteries, which supply the heart muscle. Its cause is unknown, but a viral trigger is one idea. It's also more common than you'd think - every pediatrician has seen it more than once.

Second, what's TSS? It's the effect of an infection (classically staph on the skin) producing a toxin that can make patients really sick and sometimes need an ICU to help keep their blood pressure up. Again, somewhat rare but more common than you'd think.

KD and TSS have overlapping but distinct presentations, and this new Pediatric Multisystem Inflammatory Syndrome (#PMIS) seems to sit sort of between them, though some features don't match either. I liked this summary from @redwings54:

https://twitter.com/redwings54/status/1259600053590786050

@redwings54 For reasons we don't fully understand, some kids get extremely ill ("viral sepsis") from common viruses, while their contacts have mild disease. Each winter we see this with RSV and influenza, but it could be any virus, as below. It's rare, but it's real.

pediatrics.aappublications.org/content/145/1/…

The UK report on #PMIS suggests these patients have elements of KD (high fever, coronary inflammation, rash, conjunctivitis), TSS (fever, hypotension, shock), and viral sepsis (multi-organ dysfunction), but that none of these really capture it all.

thelancet.com/journals/lance…

"But back up! I thought kids don't get COVID-19."

COVID does seem to be much less common and much less severe in kids, but some are still affected. Kids make up 2-5% of infections and about 95% have asymptomatic or mild disease. Nice references here:

journals.lww.com/pccmjournal/Ab…

"But some of these kids tested negative for COVID-19, or positive for other viruses!"

PCR tests aren't perfect. False negatives, or detection of an old infection, are both possible. New clusters of a new syndrome in a new pandemic -- it's more likely related than not.

"Should I be freaking out about my kids?"

This syndrome remains somewhat rare, so not yet. NYC found 15 #PMIS cases in a 2-week period in which there were hundreds of COVID hospitalizations a day.

www1.nyc.gov/assets/doh/dow…

www1.nyc.gov/site/doh/covid…

But if you're worried about your child for any reason, please call your pediatrician for guidance. We're still here to care for your kids, and they can get sick with any number of things, not just COVID-19 and #PMIS.

And please: wash your hands, wear a mask in public, and help protect those around you.

Any additional thoughts appreciated!

cc @CHPBugDoc, @mcfreeID, and #PedsICU folks

@CHPBugDoc @mcfreeID New data on COVID+ patients in North American pediatric ICUs:

48 pts in a 3-week period across 46 ICUs

83% had significant pre-existing medical problems.

>75% are now home or mild/moderately ill while 5% have passed and ~20% are still very sick.

jamanetwork.com/journals/jamap…

@CHPBugDoc @mcfreeID Given the scale of the pandemic in adults, this is a small number of kids who end up needing PICUs. Even given how many were fragile to begin with, most are doing pretty well. I'm overall encouraged by this early data.