1 Chapter 1 Toxins

Taken from Slayers, Saviors, Servants, and Sex: An Exposé of Kingdom Fungi by David Moore; published by Springer-Verlag, New York: 2001, ISBN 0387950982. Chapter 1 Toxins - kill the primates, rule the world. Or: Don’t turn your back on a fungus! Like most little girls being taken to their grand-parents for a Sunday treat, Innocenta probably bounced around in the back of the car like an over-excited rabbit. Just three years old, she was the only native-born American in the family. Her parents and grandparents had immigrated to southern Illinois several years before. Now, after a recent move to the Gulf coast of Mississippi, they were having a family get-together one Sunday in 1995. Grandfather particularly liked their new home because the wooded hillsides inland from the coast reminded him of home. He had taken readily to roaming through the woods and had found many plants and mushrooms he recognized as being the same as those that he and his wife had collected back in the old country for more than thirty years. Amazingly, the locals didn’t seem to be interested in this natural harvest and he had begun to collect again for his wife’s cooking. For this special day he had found a good crop of succulent mushroom caps to collect with which his wife prepared breaded and deep fried wild mushrooms as a novelty dish for her family’s Sunday brunch. The day went well until about twelve hours after the meal when four of the five family members who had eaten the mushrooms were rushed to the local hospital’s emergency department with nausea, watery diarrhoea, and abdominal pain. Grandfather did not have any symptoms and refused medical treatment. The medical staff in the emergency department realized the possible significance of the meal of mushrooms and treated their patients so as to relieve their symptoms. Giving intravenous fluids and anti-emetics. Importantly, they also monitored liver function and when liver enzyme abnormalities were recognized the next day, all four patients were transferred to the medical centre at the University of South Alabama. Meanwhile, an expert on mushrooms from the State of Mississippi Toxicology Laboratory had been called to examine mushroom specimens collected by Grandfather. He examined them in detail and identified them as the Fool’s Mushroom, which is known scientifically by the name Amanita verna. The family members were all suffering from mushroom poisoning. At the time they were transferred to the University medical centre, all four patients had normal vital signs and were free of symptoms. But the continued medical concern was over the possibility that toxins still coursing through their blood streams were doing irreparable damage to their livers. The function of this body organ is to remove toxins from the blood, but by removing and concentrating them it is itself in great danger of toxin damage. So liver function was closely monitored in all patients and abnormalities found which reached a peak about two to three days after that unfortunate meal. The patients were treated with intravenous fluids to keep their electrolytes in proper balance, with drugs to control bowel movements, and activated charcoal to absorb and remove the remaining toxins from their guts to give some help their livers with toxin removal. The three adult patients were at their worst about two days after the meal but began to recover during the next two days. Innocenta was not so lucky. Although she was free of symptoms three days after the meal, the little girl’s liver was in rapid decline and just one day later the child was transferred to a liver transplant unit where she was listed for an emergency transplant. On day five she required ventilator support, on day seven she was removed from the transplant list when she developed pneumonia. She died from sudden liver failure and general infection on day eleven. This tragic story is likely to be repeated more frequently as time goes on. ‘Natural’ foods have 1 © David Moore 2001 Taken from Slayers, Saviors, Servants, and Sex: An Exposé of Kingdom Fungi by David Moore; published by Springer-Verlag, New York: 2001, ISBN 0387950982. become much more fashionable and their increasing popularity has already lead to an increased incidence of mushroom poisoning among the general population. An incidence which will probably continue to rise. Ironically, though, mushroom poisoning often occurs in experienced collectors. On the European mainland amateur mushroom hunting is a popular pastime which has been practiced for centuries, yet this region has the highest reported incidence of mushroom poisoning in the world. In the United States, too, mushroom poisonings have been increasing since the 1970s in step with changing fashion. Not only are natural foods generally thought to be more wholesome, with wild mushrooms being especially promoted as ‘gourmet delights’ in magazines, cook books and restaurants, but the ‘alternative’ use of mushrooms - for their hallucinogenic effects - has also tempted more people into mushroom collecting. Yet the problem is not limited to those new to mushroom hunting. A Chinese magazine reported large scale mushroom poisoning among villagers in Yunnan province in central China. Sixty-one people were engaged in making a plantation on a hillside on June 28 1997. During the day fifty of them collected mushrooms for a communal meal in the evening. These were people who have lived with and used mushrooms throughout their lives, yet the mistake was made. Poisonous mushrooms were included in the meal. The first illness occurred at 6 am the following day and the first death, of a pregnant woman, occurred on 30 June. By July 1, fifty-one of the villagers showed symptoms of food poisoning (ten people had been too busy to take part in the meal!), and a total of twenty-six of them died. Subsequently, Amanita verna and the Death Cap, Amanita phalloides, were identified as being in the collection used for the meal. By all accounts, a very similar tragedy was narrowly averted in Italy in 1984 when a mycologist spotted the Death Cap (Amanita phalloides) on sale in Potenza market. He saved the town from catastrophe by making radio and TV broadcasts and touring the town by car, warning the locals of the danger by loud-speaker. It is this close resemblance between poisonous and edible, even delicious, mushrooms that creates the problem. A little knowledge can be dangerous and even experts get it wrong. The 1991 edition of the authoritative Larousse Encyclopedie had to be recalled because the illustrations of deadly amanitas were labelled ‘indifferent’ rather than ‘poisonous’. By the time the error was noticed, 180,000 volumes had been distributed and 250 people had to be hired to visit 6,000 book stores in France, Belgium, Switzerland and Canada to overprint the correct wording on the right page. In fact, fairly few mushrooms are poisonous to humans - fewer than fifty of the more than two thousand species of mushrooms which are commonly listed as occurring in most countries can be considered poisonous, and only about six are deadly. In a sense this point is irrelevant because, unfortunately, most serious poisonings are due to the very species of Amanita which contain two of the most potent toxins known, cyclic peptides called amatoxin and phallotoxin. Amanita phalloides, is aptly named Death Cap because it accounts for more than ninety percent of fatalities in the United States and Western Europe, and the other two deadly species are Amanita verna, and Amanita virosa (the common name for which is the Destroying Angel). Both of the toxins interfere with basic aspects of normal cell biology. Amatoxins bind to the RNA polymerase enzyme and interfere with production of the messenger-RNA molecules which take the genetic information from the genes themselves to the protein manufacturing machinery in the cell. With this process stopped by amatoxin, the cell is unable to produce vital working proteins. The cell cannot function properly and so it breaks down and eventually dies. Body organs which normally have high rates of protein synthesis are particularly sensitive to this toxin. Liver cells (called hepatocytes) are in this group and are most commonly involved in mushroom poisoning, but other target organs include kidney, pancreas, testes, and white blood cells. 2 © David Moore 2001 Taken from Slayers, Saviors, Servants, and Sex: An Exposé of Kingdom Fungi by David Moore; published by Springer-Verlag, New York: 2001, ISBN 0387950982. Phallotoxin causes irreversible disruption of the cell membrane and cytoskeleton and cell death inevitably results. Phallotoxin is not absorbed from the human gut, so is not thought to be responsible for the symptoms associated with human poisonings. Amatoxins are readily absorbed from the gut and are then concentrated in the liver where they do their damage. A patient poisoned with Amanita goes through four characteristic phases. For the first six to twenty-four hour the patient is free of symptoms; then there’s a twelve to twenty-four hour period of severe abdominal cramps, nausea, vomiting, and profuse watery diarrhoea. In this stage patients are often misdiagnosed as having gastric influenza, and as in the third phase the patient’s gastrointestinal symptoms improve over a further twelve to twenty-four hour period this misdiagnosis may seem to be right and the patient appears to be on the way to recovery. But all through this time the toxin is damaging the liver; killing its cells and literally ripping it apart from within. Symptoms of liver damage only appear four to eight days after the toxin was consumed, but the liver damage can progress rapidly. Accelerating all the time. Death from catastrophic failure of the liver can occur anything from six to sixteen days after the fatal meal was consumed.

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