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Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

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Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#21

Post by jeremy151 »

Tarsul wrote: post #6

This is (probably) not a Long Covid story but I found that bloodletting (for which I even received money!) gave me back the energy that I was missing for the last few years (e.g. it was impossible to build stamina). I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for som…

I live in an area with PFAS contaminated ground water (which I now aggressively filter.) To me giving blood just kind of makes sense, if there is a class of things that can enter your blood and never leave, and does not replicate on its own, why not perform a regular "oil change" and hopefully help some people at the same time. Some study has been done:

https://pmc.ncbi.nlm.nih.gov/articles/PMC8994130/

The study specifically does not look at the effect on recipients, though the donation centers do not disallow such donations. My presumption is that the donation is a net positive all around. If study comes to show the contrary, I'll certainly revise my approach.

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#22

Post by Thorrez »

tgsovlerkhgsel wrote: post #10

The paper claims that 1/5 of people experience Long COVID after an infection. Given that approximately everyone has caught COVID by now, this does not track with how rarely I've heard of people with it. Wikipedia lists much lower numbers on https://en.wikipedia.org/wiki/Long_COVID (6–7% in adults, ~1% in children, less after vaccination.) and seems to use a more liberal definition than this paper, as it mentions "Mos…

>after an acute SARS-CoV-2 infection.

Maybe not all infections are considered "acute".

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#23

Post by cheschire »

tgsovlerkhgsel wrote: post #10

The paper claims that 1/5 of people experience Long COVID after an infection. Given that approximately everyone has caught COVID by now, this does not track with how rarely I've heard of people with it. Wikipedia lists much lower numbers on https://en.wikipedia.org/wiki/Long_COVID (6–7% in adults, ~1% in children, less after vaccination.) and seems to use a more liberal definition than this paper, as it mentions "Mos…

A lot of symptoms of long covid mirror the symptoms of unhealthy living, which may make it so people either dismiss their own symptoms and don't seek diagnosis, or their complaints are dismissed by others for needing to simply improve externalities.

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#24

Post by mort96 »

spockz wrote: post #8
Tarsul wrote: post #6

This is (probably) not a Long Covid story but I found that bloodletting (for which I even received money!) gave me back the energy that I was missing for the last few years (e.g. it was impossible to build stamina). I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for som…

The lower blood pressure I can explain by having a lower volume of blood. But the glucose and cholesterol have to go somewhere. Where do they go? Are they filtered in the process after blood letting?

If it's in the blood, doesn't it just leave the body together with the blood?

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#25

Post by Thorrez »

mkoubaa wrote: post #12
Tarsul wrote: post #6

This is (probably) not a Long Covid story but I found that bloodletting (for which I even received money!) gave me back the energy that I was missing for the last few years (e.g. it was impossible to build stamina). I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for som…

If this were the case you could do a natural study on this by comparing menstruating women with the rest of the population

When people donate blood, on average they donate about 10x as much as a woman typically loses during menstruation.

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#26

Post by Ozzie_osman »

tgsovlerkhgsel wrote: post #10

The paper claims that 1/5 of people experience Long COVID after an infection. Given that approximately everyone has caught COVID by now, this does not track with how rarely I've heard of people with it. Wikipedia lists much lower numbers on https://en.wikipedia.org/wiki/Long_COVID (6–7% in adults, ~1% in children, less after vaccination.) and seems to use a more liberal definition than this paper, as it mentions "Mos…

The paper says "One in five children." I wouldn't be surprised at all. Children are very dynamic, changing often as they grow and go through different developmental stages (which may include periods where they seem more tired or more cranky, etc) . They also often lack the language and agency to explain what's going on with their bodies.

I don't see how you'd know the exact number without a solid diagnostic check.

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#27

Post by diffeomorphism »

Zak wrote: post #16
diffeomorphism wrote: post #4

94% accuracy sounds extremely bad, no? https://www.ssph-journal.org/journals/public-health-reviews/... > Prevalence estimated (...) 2%–3.5% in primarily non-hospitalized children. So a fake test always saying "No" would be more accurate at 96.5% accuracy.

The sensitivity of such a test would be 0. This test had a sensitivity of 91% versus 61% for the glass slide count method, which is a large improvement. The sample size is pretty small here and the control group even smaller. The paper concludes that a larger study is necessary to confirm the result.

That is exactly why I gave that example. Why does the headline focus on accuracy then?

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#28

Post by aesh2Xa1 »

mort96 wrote: post #24
spockz wrote: post #8

Earlier quoted context omitted.

The lower blood pressure I can explain by having a lower volume of blood. But the glucose and cholesterol have to go somewhere. Where do they go? Are they filtered in the process after blood letting?

If it's in the blood, doesn't it just leave the body together with the blood?

Yes, but the relative amount per volume blood should be the same. I think that's why he's asking.

If so, the answer is that the body replenishes plasma in a day and red cells in six weeks (redcrossblood.org FAQ). The relative amount does change quickly.

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#29

Post by shawabawa3 »

diffeomorphism wrote: post #4

94% accuracy sounds extremely bad, no? https://www.ssph-journal.org/journals/public-health-reviews/... > Prevalence estimated (...) 2%–3.5% in primarily non-hospitalized children. So a fake test always saying "No" would be more accurate at 96.5% accuracy.

Accuracy is a nonsense word in this context

Tests have a sensitivity (1 - percentage of false negatives) and specificity (1 - percentage of false positives)

"Accuracy" usually refers to sensitivity. If specificity is near 100% and the test is cheap/fast even low sensitivity can be good

On the other hand you could have sensitivity of 100% but the test could be useless if specificity is low and the condition is rare

Re: Quantification of fibrinaloid clots in plasma from pediatric Long COVID patients

#30

Post by aesh2Xa1 »

Thorrez wrote: post #25
mkoubaa wrote: post #12

Earlier quoted context omitted.

If this were the case you could do a natural study on this by comparing menstruating women with the rest of the population

When people donate blood, on average they donate about 10x as much as a woman typically loses during menstruation.

I looked up the amount of blood lost due to a menstruation cycle, and the answer is around 50 ml.

OP's linked paper has "the iron-reduction patients had 300ml of blood removed at the start of the trial and between 250 and 500ml removed four weeks later."

A blood donation removes 500 ml, so about a year of menstruation all at once. You can donate every two months, besides.

So, yes, if there is an effect then we might expect the magnitude of the effect to differ. Or else we'd expect a paper cut to also have the same effect.

Sex biological difference could matter as well.

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