Blistering red welts. A rash that spreads from the back of the hands to the neck, legs, back and abdomen. Is it poison oak? No — it's shiitake dermatitis, a bizarre reaction to eating raw or undercooked shiitake mushrooms.
Have you ever heard of this?
More common in Asia, shiitake dermatitis is thought to be a reaction to a component of the mushroom called lentinan, which breaks down when heated. Not everyone is susceptible; in one study, only nine patients out of about 500 developed a rash after contact with lentinan. Interestingly, because the response is not triggered by the immune system, it is considered a toxic reaction rather than an allergy.
The New York Times Magazine recently ran a story about a woman diagnosed with shiitake dermatitis, alerting us to this strange condition. Although fully cooked shiitakes can be safely eaten even by those who react to lentinan, one rash was enough for her: “I’m never going to touch another shiitake."
• Check it out: Diagnosis: A Red Scare - New York Times Magazine
Have you ever heard of anyone with this condition? Does it make you think twice about eating a raw shiitake mushroom?
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It doesn't sound very dangerous from the articles, so I don't see why it would scare anyone off from trying raw shiitake. It's fairly rare, so you're very unlikely to get it, and if you're one of the rare folks who do, all the better to know that you get that reaction!
It IS very dangerous. Friends of mine experienced this several years ago, and they got this rash and welting IN THEIR MOUTHS AND THROATS. They had decided to sprinkle powdered, dried shiitake mushrooms on pasta as a topping. The kids recovered OK, but the parents were ill for weeks. Until I read this week's article in the NYT I had never heard of anyone else having this issue. Based on my friends' experience, I would never eat raw shiitakes.
Never heard of it. I generally don't care for any type of uncooked mushroom, so I probably won't ever encounter a raw shiitake in my kitchen. That said, if I did come across one at a restaurant/some sort of event, I wouldn't hesistate to try one. The odds are pretty decent that I'm not.
Several times, I developed a few nasty cases of phytophotodermatitis from working with parsely in sunlight. (the chemicals in the plant make skin hypersensitive to ultraviolet light, and the result is a blistering rash)
Now I just wear gloves when I work with parsley/other plants that may cause it, and wash my hands/arms immediately after. I no longer have any problems.
I have never had any skin reactions to mushrooms. Though on occasion after eating mushrooms (raw or cooked) I will get a terrible stomachache unlike any other I've ever had until I expel the mushrooms. I love mushrooms but it does make me leery of them since I'm not sure what is actually the cause since at times there will be absolutely no reaction.
Wow, I think I had this when I was living in Japan! There was a day I had some shiitake mushrooms (amongst many days, for that matter), but I may have had them raw, something I never do. I ended up in the hospital with a rash covering my torso and abdomen, legs, etc. It was a kind of searing itch that lasted for a couple of days and when I couldn't bear it anymore I saw a doctor. After a few days on antihistamines and steroids, I was ok-- but the doctors seemed to have no idea what it was, and the biopsy (!!!) came back inconclusive.
That hasn't stopped me from eating them, though I usually buy them dried. I'll keep this in mind if it ever appears again.
I don't have it with mushrooms, but have something similar with some types of squash. My fingertips get a numb, papery rash on them. It's like if you get super glue on your skin. It goes away in a few hours. Very strange.
@James - alcohol? Some mushrooms (certain wild ones especially) cam cause serious stomach upset if consumed within several hours or even days of alcohol, and I bet some people are more sensitive than others to the phenomenon.
Wow. We buy organic shitakes from our local farmers market every week by the pound, and I often eat them raw. I never knew that there was any reason to be worried. Guess I'm not allergic!
I have developed these symptoms twice in the past 2 weeks from eating raw but dried and re-constituted shitake mushrooms. My girlfiend developed the same rash the second time also... I'm sure it is this condition, As I've never had anything like this before, apart from when I was travelling in China about 6 months ago...
This "Red Scare" is real, and it starts with acute, severe diarrhea. Some 36 to 48 hours later after consuming raw, shiitake mushrooms, the incredible rash and welting break out on your chest and quickly spread to buttocks, arms, legs, scalp and face. Unbearable itching persists for two weeks or better and I should know. After an emergency room visit to doctors who had never seen this, I basically self-diagnosed from the internet knowing that I had eaten raw, shiitake mushrooms. This red rash continues to march all over your body and can really put a fear in your head that your kidneys, liver or other organ might shut down if you go to sleep. Mine was headed toward my eyes and found its way into the socket eyelids and on the bridge of the nose. Waking up blind was the fear that sent me to the ER. After steroid injections and a pill regimen, seeing the doctor again today after two weeks of this will prove to him that it doesn't just go away on its own. And the itch continues!