Poor bastard must have been itchy as fuck. Sadly the article on a shitty ad infested site is also padded out for word count. So here is the important parts. Hand-summarised, unlike the AI-assisted article:

A 72-year-old man presented with a 2-day history of an itchy, linear rash across his back. Two days before symptom onset, he had prepared and eaten a meal containing shiitake mushrooms. - Paywalled report from New England Journal of Medicine
Caused by the carbohydrate lentinan which triggers the release of interleukin-1 (and other chemicals), which causes cause inflammation.
The rash develops usually 2-3 days after eating undercooked shiitake.
Lentinan is broken down when thoroughly cooked at temperatures over 145° C / 293° F

Because fuck shitty pop-science padded journalism and their marketing strategies and hostile UX, and fuck the NEJM too for paywalling medical research.

[–] ToxicWaste@lemm.ee 11 points 1 year ago (2 children)

Not sure if the 145°C is a citation/translation error by the site. If the mushroom is boiled in water (e.g. hotpot), it will never reach those temperatures.

[–] fiat_lux@kbin.social 9 points 1 year ago

I got it from the quote in the article from the author of the NEJM paper. You're correct, but this seems to also happen in maybe 2% of people, and there's a good chance 145C is only needed to be absolutely certain all sugars have 100% broken down. Hotpots might still get rid of most of it at 100C. I'm not a polysaccharine decomposition expert though, even though I know they're very heat-sensitive.

If you're really worried (which you probably don't need to be given it's rarity), mushrooms can't really be overcooked (unless you literally burn them), so nuking them in the microwave with a thin coat of oil or frying them off will help get them to temp if you want to be really certain.

Second source from non-paywalled:

It affects about 2% of people that consume the mushrooms raw or only lightly cooked... in people of all ages, ... more often male than female.
...shiitake dermatitis is not seen with the ingestion of thoroughly cooked at a temperature > 145 C.
- Shiitake flagellate dermatitis

[–] Skelectus@suppo.fi 4 points 1 year ago

Searched for it, multiple sites give 130-145°C.

[–] mayonaise_met@feddit.nl 19 points 1 year ago* (last edited 1 year ago) (2 children)

This could be a House episode. Girl comes in with whipped back. House suspects abuse, which turns out to be correct, but the wound is because of Shiitake.

[–] lagomorphlecture 3 points 1 year ago

And, of course, the girl lies about mushrooms because reasons and they have to break into her house to solve the case.

[–] tesseract 1 points 1 year ago

The article says that it was not caused by scratching the itches. But the pattern is exactly like as if he scratched with his nails. Perhaps his back became tender and sensitive due to the mushrooms and scratching created the patterns.

[–] deegeese@sopuli.xyz 13 points 1 year ago

I always cook shiitakes because it tastes better, but you’ve given me an even better reason.

[–] PlasmaDistortion@lemm.ee 12 points 1 year ago (1 children)

Rare? Uhhh this happened to me a few years ago. We bought some dehydrated shiitake mushrooms from Costco. They were absolutely delicious and I ate a handful of them.

Within about 4 hours I had red hive like marks all over my body and it hurt to wear any clothing or touch anything. The pain was absolutely excruciating and nothing dulled it. My doctor said it was mushroom toxicity and I would just have to “wait it out”. Well that took about 6 days to get it out of my system.

To this day I have avoided eating any mushrooms raw.

[–] tesseract 1 points 1 year ago

Costco shiitake mushrooms shouldn't be toxic at all. Otherwise, so many would be dead by now - at least a few people would have eaten too much before the toxicity showed up. Perhaps you are badly allergic to it? That happens to a few people to common and safe food.

[–] variants@possumpat.io 8 points 1 year ago

The last of us begins

[–] rauls4@lemm.ee 7 points 1 year ago

Thanks. I hate it.

[–] Kolanaki@yiffit.net 7 points 1 year ago (1 children)

Hm... Because of the season, I've been watching a lot of spooky stuff and now I am considering how reports of being scratched by ghosts or demons could be stuff like this condition. Some kind of reaction to something leaving marks that look like scratches, when they aren't really. 🤔

[–] fiat_lux@kbin.social 5 points 1 year ago

They're probably scratches though, just on skin that is very angry about being scratched. The case report said he was scratching in his sleep, and if you look at the pattern, it lines up with the ability to reach certain spots and what orientation his hands would need to be in to scratch those spots.

Otherwise your theory works. A bunch of people scratching themselves in their sleep and then freaking out over the results.

[–] ivanafterall@kbin.social 7 points 1 year ago (1 children)

This man couldn't begin to honestly explain his new hobby to his sweet, delicate Mildred. Thus "shiitake dermatitis" was born in a stroke of genius.

[–] BlueEther@no.lastname.nz 3 points 1 year ago

Is that you Mr Larson?

[–] Diplomjodler@feddit.de 7 points 1 year ago (4 children)

How the fuck do I cook something at 145°C?

[–] fiat_lux@kbin.social 13 points 1 year ago (1 children)

Add a little oil, and a few minutes in a frying pan or microwave will do it. Maillard reaction (browning) starts at around 140°C and shiitake aren't exactly thick, so they won't take much longer than it takes to get some extra colour on them. Average frypan and oven temp is usually around 180°C, so it's not something you really need to think or worry about.

They also think you need a certain hypersensitivity for this to happen. If this were a significant risk, there would be huge amounts of cases in East Asia. This case became a science tabloid spam piece because it's so unusual.

[–] CanadaPlus@lemmy.sdf.org 1 points 1 year ago

It's kind of crazy how much pressure you'd need to brown something in a wet environment. I've never thought about it that way, it puts it into perspective. Thanks Lemmy!

[–] harry315@feddit.de 5 points 1 year ago* (last edited 1 year ago)

Easy. Just pressure cook it at 4.5 bar (65 Psi) in your industrial grade pressure cooker.

Being realistic, I guess someone accidentally swapped Celsius and Farenheit?

EDIT: Nope, seem to be wrong. They do mean 145 degC. On the other hand, I found a source reporting that 57 % of a total of 58 cases of shiitake dermatitis actually thoroughly cooked their mushrooms. Cooking won't save you from this, as it seems.

Study: Ha, JH; Byun, DG; Kim, SM; Yoo, CH; Park, CJ (2003): Shiitake dermatitis in Korea; clinical and histopathologic study. Korean J. of Dermatology, Vol.41 (4),pg 440 – 444

[–] clutchmattic 4 points 1 year ago

Thermite

[–] filcuk@lemmy.zip 2 points 1 year ago (1 children)

Average stove gets to around 350°C. Electric can go to 900. Gas up to 2000, depending on the mixture used.

[–] KSPAtlas@sopuli.xyz 5 points 1 year ago (1 children)

Wouldn't gas just liquefy the pot in that case?

[–] filcuk@lemmy.zip 4 points 1 year ago

I think gas is less efficient in heat transfer, but electric does melt aluminium pots (if dry).

[–] state_electrician@discuss.tchncs.de 2 points 1 year ago

Shitache mushrooms https://youtu.be/HpUn9tzwj2E?si=sJ6JQEj3gHWVU-6U

[–] Yazer@lemmy.ca 1 points 1 year ago

That's shiita

[–] Pantherina@feddit.de 1 points 1 year ago

I know Lions mane in high doses can make your skin also itchy as hell

[–] theodewere@kbin.social 1 points 1 year ago (1 children)

man that dude's back looked like somebody beat him with a whip or something, that was nasty

[–] MummifiedClient5000@feddit.dk 1 points 1 year ago

I swear I'm not a perv, it must be something I ate.