The Yellow Knight Fights Back: Toxicological, Epidemiological, and Survey Studies Defend Edibility of Tricholoma equestre

Comment on "Mushroom intake and depression: A population-based study using data from the US National Health and Nutrition Examination Survey (NHANES), 2005-2016"

The collection of wild mushrooms for consumption remain highly popular in different populations and is also practiced in the US. It cannot be ruled out that the decreased (not dose-dependent) odd of depression in mushroom consumers is, at least partially, due to their exposure to the natural environment and associated lifestyle factors. Therefore, further research focusing on depression rates in groups of mushroom hunters is encouraged.

A comparison of toxic and essential elements in edible wild and cultivated mushroom species

The multi-elemental composition of 4 edible wild-growing mushroom species that commonly occur in Polish forests was compared to 13 cultivated mushroom species available in trade. A considerable variation in the macroelements content was revealed with cultivated species containing higher amounts of macroelements. The mean content of B, Co, Cr, Fe, Pb, Pr, Pt, Sb, Sm, Sr, Te, and Tm was higher in cultivated mushroom species, while the opposite was noted for Ba, Cd, Cu, Hg, La, Mo, Sc, and Zn. Selected cultivated forms exhibited increased content of Al (F. velutipes), As (H. marmoreus, F. velutipes), Ni (P. ostreatus, A. polytricha, H. marmoreus), and Pb (P. ostreatus, A. polytricha, F. velupites, and L. edodes). Wild-growing species, B. boletus, I. badia, and S. bovinus contained high Hg levels, close to or exceeding tolerable intakes. Compared to cultivated mushrooms, they also generally revealed a significantly increased content of Al (with the highest content in B. edulis and I. badia), As and Cd (with the highest content in B. edulis and S. bovinus in both cases). In turn, the cultivated mushrooms were characterized by a higher content of Ni (particularly in A. bisporus) and Pb (with the highest content in P. eryngii). The exposure risks may, however, differ between wild and cultivated mushrooms since the former are consumed seasonally (although in some regions at a high level), while the latter are available throughout the year. Both cultivated and wild-growing mushrooms were found to be a poor source of Ca and Mg, and only a supplemental source of K, Cu, Fe, and Zn in the human diet. These results suggest that mushrooms collected from the wild or cultivated, should be consumed sparingly. The study advocates for more strict monitoring measures of the content of toxic metals/metalloids in mushrooms distributed as food, preferentially through the establishment of maximum allowance levels not limited only to a few elements and mushroom species.

Mushroom Poisoning

BACKGROUND

Poisonous mushrooms are eaten by mushroom hunters out of ignorance, after misidentification as edible mushrooms, or as a psychoactive drug. Mushroom poisoning commonly leads to consultation with a poison information center and to hospitalization.

METHODS

This review is based on pertinent publications about the syndromes, toxins, and diagnostic modalities that are presented here, which were retrieved by a selective search in PubMed. It is additionally based on the authors' longstanding experience in the diagnosis and treatment of mushroom intoxication, expert consultation in suspected cases, macroscopic identification of wild mushrooms, and analytic techniques.

RESULTS

A distinction is usually drawn between mushroom poisoning with a short latency of less than six hours, presenting with a gastrointestinal syndrome whose course is usually relatively harmless, and cases with a longer latency of six to 24 hours or more, whose course can be life-threatening (e.g., phalloides, gyromitra, orellanus, and rhabdomyolysis syndrome). The DRG diagnosis data for Germany over the period 2000-2018 include a total of 4412 hospitalizations and 22 deaths due to the toxic effects of mushroom consumption. 90% of the fatalities were due to the death cap mushroom (amatoxins). Gastrointestinal syndromes due to mushroom consumption can be caused not only by poisonous mushrooms, but also by the eating of microbially spoiled, raw, or inadequately cooked mushrooms, or by excessively copious or frequent mushroom consumption.

CONCLUSION

There are few analytic techniques available other than the qualitative demonstration of amatoxins. Thus, the diagnosis is generally made on the basis of the clinical manifestations and their latency, along with meticulous history-taking, assisted by a mushroom expert, about the type(s) of mushroom that were consumed and the manner of their preparation.

Reviewing the world's edible mushroom species: A new evidence-based classification system

Wild mushrooms are a vital source of income and nutrition for many poor communities and of value to recreational foragers. Literature relating to the edibility of mushroom species continues to expand, driven by an increasing demand for wild mushrooms, a wider interest in foraging, and the study of traditional foods. Although numerous case reports have been published on edible mushrooms, doubt and confusion persist regarding which species are safe and suitable to consume. Case reports often differ, and the evidence supporting the stated properties of mushrooms can be incomplete or ambiguous. The need for greater clarity on edible species is further underlined by increases in mushroom-related poisonings. We propose a system for categorizing mushroom species and assigning a final edibility status. Using this system, we reviewed 2,786 mushroom species from 99 countries, accessing 9,783 case reports, from over 1,100 sources. We identified 2,189 edible species, of which 2,006 can be consumed safely, and a further 183 species which required some form of pretreatment prior to safe consumption or were associated with allergic reactions by some. We identified 471 species of uncertain edibility because of missing or incomplete evidence of consumption, and 76 unconfirmed species because of unresolved, differing opinions on edibility and toxicity. This is the most comprehensive list of edible mushrooms available to date, demonstrating the huge number of mushrooms species consumed. Our review highlights the need for further information on uncertain and clash species, and the need to present evidence in a clear, unambiguous, and consistent manner.

Toxicological risks and nutritional value of wild edible mushroom species -a half-century monitoring study

The content of major- and trace elements in wild-growing mushrooms has been subject to numerous studies, but the data on long-term trends in this regard are scarce. The aim of research was to determine the content of 34 elements in four edible mushroom species Boletus edulis, Imleria badia, Leccinum scabrum and Macrolepiota procera, and associated soil collected from Polish forests between 1974 and 2019. As initially hypothesized, the element concentration in the studied soil revealed an increasing trend and was positively correlated with their levels found in fruit bodies. Bioconcentrafion Factor values exceeding 1 were documented for all mushroom species for K, P, Ag, Cd, Cu, Hg, and Zn. When compared to the Adequate Intakes, all the mushroom species were found to be a good dietary source of K, P, and Zn (range of 6260-8690, 6260-8690 and 97-135 mg kg^-1 dry weight (dw), respectively), and B. edulis and I. badia a moderate source of Fe (mean 71.5 and 76.5 mg kg^-1 dw, respectively), B. edulis of Mn and Mo (mean 20.0 and 0.42 mg kg^-1 dw, respectively), while L. scabrum and M. procera a source of Cu. Consumption of the studied mushrooms would not lead to significant exposure to Al, As, Cr, or Ni. Considering that wild mushrooms will continue to be collected in Poland, one should bear in mind that they are a limited source of minerals in the human diet while their frequent, regular consumption, associated with exposure to selected toxic elements, should not be recommended.

Myotoxic Mushroom Poisoning in Thailand: Clinical Characteristics and Outcomes

Purpose

To describe the clinical characteristics and outcomes of myotoxic mushroom poisoning in Thailand.

Patients and Methods

We performed a retrospective cohort study of cases of myotoxic mushroom poisoning from the Ramathibodi Poison Center Toxic Exposure Surveillance System during a 5-year period (2012-2016).

Results

Forty-one cases were included. Most (53.7%) were male with the average age of 49 years. In three cases, the mushrooms were identified as Russula species by an experienced mycologist. Common presenting symptoms were gastrointestinal (GI) symptoms and myalgia. The median onset of GI symptoms and symptoms suggesting rhabdomyolysis after consuming mushrooms was 2 hours (0.17-24 hours) and 24-48 hours (2-120 hours), respectively. Eight patients who ate the mushrooms together with other patients with rhabdomyolysis had GI symptoms but did not develop rhabdomyolysis. For patients with rhabdomyolysis, acute kidney injury (AKI) and hyperkalaemia occurred in 51.5% and 33.3% of cases, respectively. Median initial and maximum creatine phosphokinase (CPK) levels in patients with rhabdomyolysis were 31,145 and 47,861 U/L, respectively. Fifteen of 17 patients who were investigated for troponin levels had elevated troponin. Three patients had a low ejection fraction. Most patients (95.1%) were admitted to hospital, with a median stay of 5 days. The mortality rate was 26.8%. Treatments included intravenous fluid, urine alkalinization, haemodialysis and peritoneal dialysis. Among patients with rhabdomyolysis, AKI, hyperkalaemia during hospitalisation, maximum CPK level, maximum creatinine level and initial and maximum potassium levels were the factors found to be significantly different between patients who died and those who survived.

Conclusion

Myotoxic mushroom poisoning had a high mortality rate. Most patients had early or delayed onset of clinical symptoms after mushroom ingestion. Some patients developed severe cardiovascular effects. Early detection, close monitoring (especially serum potassium, creatinine, CPK and cardiac effect) and good supportive care were the main treatment modalities.

Toxic Potential of Traditionally Consumed Mushroom Species-A Controversial Continuum with Many Unanswered Questions

Mushroom poisonings remain a significant cause of emergency medicine. While there are well-known species, such as Amanita phalloides, causing life-threatening poisonings, there is also accumulating evidence of poisonings related to species that have been considered edible and are traditionally consumed. In particular, the Tricholoma equestre group was reported to cause myotoxicity. In addition, particular wild mushrooms that are traditionally consumed especially in Asia and Eastern Europe have been subject to suspicion due to possible mutagenicity. Hitherto, the causative agents of these effects often remain to be determined, and toxicity studies have yielded contradictory results. Due to this, there is no consensus about the safety of these species. The issue is further complicated by difficulties in species identification and other possible sources of toxicity, such as microbiological contamination during storage, leading to sometimes opposite conclusions about the edibility of a species. This review focuses on existing data about these types of mushroom poisonings, including the still sparse knowledge about the causative chemical agents. In addition, the aim is to initiate a meta-discussion about the issue and to give some suggestions about how to approach the situation from the viewpoint of the collector, the researcher, and the practicing physician.

From quail to earthquakes and human conflict: a historical perspective of rhabdomyolysis

Rhabdomyolysis is a common cause of acute kidney injury, featuring muscle pain, weakness and dark urine and concurrent laboratory evidence of elevated muscle enzymes and myoglobinuria. Rhabdomyolysis is often seen in elderly and frail patients following prolonged immobilization, for example after a fall, but a variety of other causes are also well-described. What is unknown to most physicians dealing with such patients is the fascinating history of rhabdomyolysis. Cases of probable rhabdomyolysis have been reported since biblical times and during antiquity, often in the context of poisoning. Equally interesting is the link between rhabdomyolysis and armed conflict during the 20th century. Salient discoveries regarding the pathophysiology, diagnosis and treatment were made during the two world wars and in their aftermath. 'Haff disease', a form of rhabdomyolysis first described in 1920, has fascinated scientists and physicians alike, but the marine toxin causing it remains enigmatic even today. As a specialty, we have also learned a lot about the disease from 20th-century earthquakes, and networks of international help and cooperation have emerged. Finally, rhabdomyolysis has been described as a sequel to torture and similar forms of violence. Clinicians should be aware that rhabdomyolysis and the development of renal medicine are deeply intertwined with human history.