Mushroom poisoning refers to the severe and often deadly effects of various toxins that are found in certain types of mushrooms. One type known as Amanita phalloides, appropriately called "death cap," accounts for the majority of cases. The toxins initially cause severe abdominal cramping, vomiting, and watery diarrhea, and then lead to liver and kidney failure.
The highest reported incidences of mushroom poisoning occur in western Europe, where a popular pastime is amateur mushroom hunting. Since the 1970s, the United States has seen a marked increase in mushroom poisoning due to an increase in the popularity of "natural" foods, the use of mushrooms as recreational hallucinogens, and the gourmet qualities of wild mushrooms. About 90% of the deaths due to mushroom poisoning in the United States and western Europe result from eating Amanita phalloides. This mushroom is recognized by its metallic green cap (the color may vary from light yellow to greenish brown), white gills (located under the cap), white stem, and bulb-shaped structure at the base of the stem. A pure white variety of this species also occurs. Poisoning results from ingestion of as few as one to three mushrooms. Higher death (mortality) rates of more than 50% occur in children less than 10 years of age.
David Kaminstein MD, The Gale Group Inc., Gale, Detroit,