The Death Cap
One side will make you grow taller, and the other side… Well, actually, no. Either side will kill you. But nonetheless, the mushroom known as the Death Cap, Amanita phalloides, is ubiquitous and accounts for the majority of fatalities caused by mushroom poisoning. A. phalloides usually grows in summer and in autumn, but since it can be harvested and stored, poisoning may occur at any time of the year. Although they have a worldwide distribution, these fungi range from Eastern North America to the Pacific Coast within the United States and are found growing in forests under a tree or in a glade. They are distinguished by a rounded to flat cap with gills underneath, and a ringed stalk.
The most crucial consideration in mushroom poisoning is patient history. The time the individual consumed the mushrooms, the time of onset of symptoms, and how many mushrooms were eaten are all important in determining the outcome. Without this information, the diagnosis and subsequent treatment are difficult. Only 20 to 50 grams of fresh mushrooms can produce critical liver and kidney damage, and just three or four mushrooms are approximately 50 grams.
A. phalloides contains amatoxins, particularly alpha and beta amanitin, which are rapidly absorbed by the intestines and bind to cellular structures within the liver, interfering with messenger RNA synthesis, which is essential for making proteins. Cells of the gastrointestinal tract, liver, and kidney have a high rate of protein synthesis and are especially susceptible to injury. Amatoxins are also thermostable, meaning that cooking, drying, and freezing do not alter their toxicity.
Amanitin poisoning is distinguished by an initial incubation stage when the patient is generally asymptomatic. Then within 6-12 (or up to 48) hours, patients present with abdominal pain, nausea, vomiting, and diarrhea (sometimes as frequently as six times per hour). Patients may develop severe dehydration, electrolyte disturbances, and increased liver function biomarkers. This phase may last 2–3 days. As toxicity proceeds unchecked, patients progress to acute hepatorenal (liver/kidney) failure, encephalopathy, coma, and finally, death.
Supportive care, including fluid treatment, is necessary, but death may occur in 50%–90% of patients without specific therapy. This is reduced to below 10% in patients receiving therapy. When medical treatment is unsuccessful, liver transplantation is used as a definitive remedy. Orthotopic liver transplantation has been successfully used in both adult and pediatric mushroom poisonings. Indications for emergency liver transplantation include a significant decrease in coagulation factors produced by the liver.
The Meixner or Wieland newspaper test requires blotting a sample of the mushroom to be tested on a piece of newspaper, adding concentrated hydrochloric acid, and observing the development of a blue color. The blue color results from a reaction of the substituted indole residue in the amanita toxins and the lignin in the paper.
A final word of caution!
To Be or Not to Be Depends on Early Therapy
A mushroom meal the eaters hits
Delayed by belly cramps and shits
Please treat as promptly as you can
To be that woman or that man
That saves the mushroom eater’s life
And all his children and his wife
!(From Zilker and Faulstich, Cyclopeptide-Containing Mushrooms: The Deadly Amanitas, Critical Care Toxicology, 2017)
Adapted with permission from Lily Robinson and the Art of Secret Poisoning (nVision Publishing)