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Toxicology Committee Annual Reports

NAMA Toxicology Committee Report for 2005
Recent Mushroom Poisonings in North America

By Michael W. Beug, Ph.D., Chair NAMA Toxicology Committee

2005 Toxicology Committee Report Compiled by Michael W. Beug, Ph.D. Toxicology Committee Chair

After a busy 2004 season with many mushroom poisonings, 2005 was a relief. We received a total of 46 reports involving 67 humans and 16 reports involving 23 dogs. I want to thank everyone who sent in reports, especially Marilyn Shaw who submitted 25 of the 62 reports.

Several dogs died in the past year due to mushroom poisoning but there were no human fatalities reported where in the final analysis mushrooms appeared to be at fault. A number of calls to poison centers came from parents whose child had mushrooms in his/her mouth or had been seen eating a mushroom. Most of these cases were asymptomatic. A few calls came in where someone ate mushrooms and then suffered a panic attack from concern that they may have made an error. It is best to confirm your identification before eating the mushroom!

There were a few first time or otherwise unique inquiries regarding mushroom poisoning. An email was forwarded to me from a person in Oregon who was concerned about a woman at a workshop who consumed a Cortinarius in the subgenus Dermocybe. She was asymptomatic but there was concern about symptoms showing up later. Orellanine poisoning is characterized by a delayed onset of 2 to 21 days and the symptoms are headache, GI distress, sweating, lethargy, anorexia, marked polyurua and polydypsia with ultimate evidence of progressive kidney failure, oliguria and anuria. However, there are no cases of orellanine poisoning ever recorded in North America, though since 1952 in Europe it has been a recognized poisoning cause when an astute Polish epidemiologist traced 102 serious poisonings and 11 deaths to consumption of certain Cortinarius species. There is still debate about what causes the orellanine poisoning but all investigators agree that the chemicals show a very strong turquoise or blue fluorescence under ultraviolet light and the fluorescence can be demonstrated not only in the mushrooms but in biopsy tissues.

A second intriguing case involved a notification of a human death from ingestion of a Gyromitra species. A couple had picked tons of "morels" and the wife, a neighbor and the husband ate them all. The husband became ill and died the next day. Further correspondence revealed that the symptoms were slurred speech, stomach pains, and dizziness. He "blacked out," vomited black stomach contents. He was very hungry and very thirsty. Liver enzyme tests were negative. The victim was an elderly man who did not believe in doctors or in going to the hospital. He had suffered diarrhea for the previous 7 months and had been nauseated for a couple of weeks prior to the mushroom meal. A review of NAMA poisoning reports for the past 30 years did not reveal any deaths attributed to consumption of Gyromitra species, thought there were 9 reports of liver damage and three cases where the kidneys failed as well. This case involved neither liver nor kidney failure and the cause of death was ultimately determined not to be the mushrooms, though they may possibly have hastened the man’s demise.

A third puzzling case involved a horse. The NAMA Mushroom Poisoning Case Registry contains no reports of horses that had been poisoned by mushrooms. Here is the situation:

I found my prize broodmare Isabeau ill with severe diarrhea and fever. She had been perfectly healthy and fit the day before. Now she wouldn’t eat or drink and was very lethargic. I called the vet immediately but despite (extensive treatment) she showed no improvement…until the 9th day… One of my forest pastures contained a larger amount of mushrooms than we had ever seen before… Have you ever had a horse owner suspect mushroom poisoning in his horses…She was tested for Potomac Horse fever, Salmonella, EPM, West Nile Virus and everything came out negative. She has no organ damage. No founder. I talked with my vet and the vets at OSU. They see cases like this every fall. Half of the horses die. No one knows what causes them… Could mushrooms be a factor in these diarrhea cases?

I had no answer. Maybe others will have a chance to examine similar cases in the future and see whether or not there is a mushroom connection in these illnesses occurring in horses.

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