Mushroom Clinical Classification Guidelines

 www.toxinology.com

In recent years the range of recognized clinical syndromes associated with mushroom poisoning has expanded and is now well beyond the scope of past classification schemes. A revised classification of mushroom poisoning syndromes is included in this website, based on 6 major groups, most with subgroups (as explained below).

Classification Scheme for Clinical Types of Mushroom Poisoning.

Group

Suspected Toxin

Explanation

Group 1 - Cytotoxic mushroom poisoning.

 This broad group encompasses just those types of poisoning where there is specific major internal organ pathology, causing either primary hepatotoxicity, or primary nephrotoxicity.

Group 1A - Primary hepatotoxicity

 Amatoxins

This subgroup encompasses toxins such as amatoxins that cause potentially lethal hepatotoxicity, with a specific constellation of clinical features. A number of mushroom species contain amatoxins in sufficient quantity to cause significant toxicity, including several Amanita spp. (eg. Amanita phalloides ), Lepiota spp. and Galerina spp.

Group 1B - Primary nephrotoxicity

AHDA

This subgroup encompasses those mushrooms causing direct renal damage as an acute effect, and is associated with mushrooms containing aminohexadienoic acid (AHDA), such as Amanita smithiana and Amanita pseudoporphyria.

Group 1C - Delayed primary nephrotoxicity

 Orellanine

This subgroup encompasses those mushrooms causing delayed renal failure, and is associated with mushrooms containing orellanine, notably some Cortinarius spp.

     

Group 2 - Neurotoxic mushroom poisoning

 This broad group includes those classic types of mushroom poisoning causing primary neurotoxicity.
Group 2A - Hallucinogenic mushrooms Psilocybins This subgroup encompasses those mushrooms causing hallucinations or related effects as the primary presenting symptom. It is associated with mushrooms containing psilocybins, psilocins, gymnopilins and related toxins, including selected Psilocybe spp., Conocybe spp., Gymnopilus spp., Panaeolus spp., Copelandia spp., Pluteus spp., and possibly Stropharia spp.
Group 2B - Autonomic toxicity mushrooms Muscarines This subgroup encompasses those mushrooms causing direct autonomic effects. It is associated with mushrooms containing muscarines and related toxins, such as selected Inocybe spp., Clitocybe spp., Mycena spp. and Rubinoboletus spp.
Group 2C - Central nervous system toxicity mushrooms Ibotenic acid/muscimol This subgroup encompasses those mushrooms causing neuroexcitatory effects, sometimes including “hallucinations”. The toxins are muscimol and ibotenic acid. A variety of mushrooms are involved, including Amanita muscaria, A. patherina, A. ibotengutak.
Group 2D - Morel neurologic syndrome Unknown This subgroup contains a currently ill-defined syndrome of neurological and GIT effects following consumption of a variety of morel mushrooms. No toxin has yet been identified as a causative agent and the status of this type of “poisoning” is unclear. Nearly all cases are associated with ingestion of Morchella spp.

Group 3 - Myotoxic mushroom poisoning

This group covers poisoning with rhabdomyolysis as the primary feature.
Group 3A - Rapid onset myotoxicity Carboxylic acid This subgroup encompasses those mushrooms causing rapid onset myotoxicity. The causative toxin has been reported to be cycloprop-2-ene carboxylic acid. It is associated with ingestion of selected Russula spp. (R. subnigricans).
Group 3B - Delayed onset myotoxicity Saponaceolide B This subgroup encompasses those mushrooms causing delayed onset myotoxicity. The causative toxins remain incompletely understood, though recent research indicates that saponaceolide B and M may potentially be the prime toxins in some cases. It is associated with ingestion of selected Tricholoma spp. such as T. equestre, possibly T. terreum, T. auratum.

Group 4 - Metabolic toxicity mushroom poisoning

 This broad group includes a wide variety of poisoning syndromes and clinical presentations, so could be considered a grouping assembled for convenience, rather than reflecting close clinical similarities.
Group 4A - GABA-blocking mushroom poisoning Gyromitrins This subgroup encompasses those mushrooms causing metabolic-based pathology secondary to blocking of GABA synthesis, resulting in multi-organ effects. It is associated with mushrooms containing gyromitrins, notably selected Gyromitra spp.
Group 4B - Disulfiram-like mushroom poisoning/td> Coprines This subgroup encompasses those mushrooms causing a disulfiram-like reaction on subsequent (post ingestion of mushrooms) consumption of alcohol. It is associated with mushrooms containing coprines, notably selected Coprinus spp.
Group 4C - Polyporic mushroom poisoning Polyporic acid This subgroup encompasses those mushrooms causing neurologic plus multi-organ effects. It is associated with mushrooms containing polyporic acid, notably Hapalopilus rutilans.
Group 4D - Trichothecene mushroom poisoning Trichothecenes This subgroup encompasses those mushrooms causing a specific syndrome of multi organ failure, particularly bone marrow failure and lamellar desquamation of palms, soles of feet and face. It is associated with mushrooms containing trichothecenes, notably Podostroma cornudamae.
Group 4E - Hypoglycaemic mushroom poisoning Unusual amino acids This subgroup encompasses those mushrooms causing rapid hypoglycaemia. It is associated with mushrooms from Yunnan, China, notably Trogia venenata. The causative toxins are reported to be unusual amino acids (2R-amino-4S-hydroxy-5-hexynoic acid and 2R-amino-5-hexynoic acid).
Group 4F - Hyperprocalcitoninemia mushroom poisoning Unknown This subgroup consists of an isolated small case series from France, where seven patients developed hyperprocalcitoninemia in association with consumption of Boletus satanas
Group 4G - Pancytopenia mushroom poisoning Unknown This subgroup encompasses a rare poisoning, described from just two cases in Japan, following prolonged consumption (over several days) of a herbal medicinal concoction made from Ganoderma neojaponicum.

Group 5 - Gastrointestinal irritant mushroom poisoning

 This is a large group, with no current subgroups, and includes a wide variety of mushrooms that cause gastrointestinal effects without causing other significant effects. This latter distinction is important clinically, because many types of mushroom poisoning cause GIT effects in addition to their primary toxicity effects.

Group 6 - Miscellaneous adverse reactions to mushrooms

 This group contains those types of mushroom “poisoning” which do not fit within the previous 5 groups. Not all are due to specific “poisoning” reactions, but from a practical clinical perspective they are included within this classification scheme.
Group 6A - Shiitake mushroom dermatitis Lentinan This subgroup encompasses those mushrooms causing acute dermatitis post ingestion. It is associated with Shiitake mushrooms (Lentinola edodes). The pathophysiology is unclear, but it appears to be non-allergic and most likely associated with a thermolabile polysaccharide, lentinan, found in these mushrooms.
Group 6B - Erythromelalgic mushroom poisoning Acromelic acid This subgroup encompasses those mushrooms causing an erythromelalgic-like syndrome. It is associated with mushroom ingestion, notably Clitocybe acromelalga/amoenolens. Acromelic acid is considered to be the causative toxin.
Group 6C - Paxillus syndrome Unknown This subgroup encompasses those mushrooms causing an autoimmune haemolytic anaemia after repeated exposure. It is associated with brown roll-rim mushrooms, specifically Paxillus spp. (P. involutus).
Group 6D - Encephalopathy syndrome ? HCN This subgroup poisoning syndrome, described from Japan, is speculatively considered to be the result of HCN poisoning following consumption of mushrooms containing high HCN levels. Mushrooms implicated in this type of poisoning include Pleurocybella porrigens, Grifola frondosa, Pleurotus eringii.