Wonder how many vendors — at all levels of the supply chain — actually know the full power of all we sell?
The New York Times Magazine runs a regular feature called “Diagnosis,” in which each article identifies a medical mystery and solves it. The pieces are written by Dr. Lisa Sanders, who authored a book titled, Every Patient Tells a Story: Medical Mysteries and the Art of Diagnosis.
This particular piece is titled A Red Scare — not referring to the fear of communists but to a horrible red rash. After thinking it might be Poison Oak and considering other possibilities, the doctors, led by a Dr. Walter Larsen from Portland, Oregon, came up with a surprising diagnosis:
“O.K. — it’s time to call in reinforcements.” Larsen asked if he could bring in a couple of colleagues and then disappeared from the room, returning a few minutes later with two of his younger partners. After a long moment, one of the partners, Dr. Michael Adler, broke the silence. He asked the patient whether she had eaten any shiitake mushrooms recently. The question surprised her. “How did you know?” she asked. On Friday, three days before the rash appeared, she was offered a sample of shiitakes cooked in oil and garlic at her local grocery store. They tasted fine, maybe a little chewier than usual, but she enjoyed them.
The young doctor thanked her, and then the three walked out of the room without telling her anything more. Finally Larsen returned. “We think this is a classic reaction to raw or undercooked shiitake mushrooms,” Larsen told her. Shiitake dermatitis, as it’s known in medical jargon, was first described in 1977. Since then, it has been frequently reported in Asia, though rarely, if ever, in the U.S. The rash is thought to be a toxic reaction to a starchlike component of the shiitake mushroom. This component, known as lentinan, breaks down with heat, and so this reaction is seen only when the mushrooms are eaten raw or partly cooked.
“So am I allergic to these mushrooms?” the patient asked. Well, it’s not a true allergy, Larsen explained. When someone is exposed to a substance and has a bad response, it’s considered allergic only when the immune system causes the reaction. Then you’ll get hives or swelling or occasionally anaphylaxis. But when people who get this rash are tested, there’s no sign of an immune response, so it’s considered a toxic, not allergic, reaction. The current thinking is that something in the lentinan triggers blood vessels to dilate and leak small amounts of inflammatory compounds just beneath the skin.
Not everyone has this kind of violent reaction to raw shiitakes. In one study, just over 500 patients were exposed to an intravenous version of lentinan. Nine developed this streaky rash. The other patients had no response. Perhaps that’s lucky for them, because this same component is thought to have important health benefits. Studies suggest that lentinan may be helpful in preventing diseases ranging from cavities to colon cancer. Why it creates these whiplike streaks in some is not well understood. A rash with a similar pattern has been linked to bleomycin, a chemotherapeutic medication.
Larsen ordered a biopsy of the rash to make sure they weren’t missing anything, and he instructed the patient to continue to use the steroid cream at home. The cream helped, but it took weeks for the rash to fade completely.
Larsen recommended she avoid uncooked shiitakes. “I’m never going to touch another shiitake,” the patient told him. “I don’t care if they are good for you. One of these rashes was enough.”
So, what is the lesson? Thinking of doing a demo? Make sure your insurance is sufficient, and if the item is Shitake mushrooms, well-cooked is imperative. And note that not knowing the power of what we sell can lose a customer for life.