Mushroom Poisoning

Aka: Mushroom Poisoning, Cyclopeptide Mushrooms

1. Epidemiology
   1. Prepared foods with toxic mushrooms is most common type of lethal exposure
2. Types
   1. Neurotoxic mushrooms
      1. Amanita muscaria and pantherina (Cholinergic Toxicity)
      2. Inocybe and Clitocybe species (parasympathetic)
      3. Coprinus atramentarius (Antabuse-like Alcohol effect)
      4. Psilcybe (Hallucinogen)
      5. Gyromitra esculenta or false morel: severe Neurotoxin
   2. Hepatotoxic mushrooms (Cyclopeptide Mushrooms)
      1. Background
         1. Amatoxins (cyclic peptides) are heat stabile with high bioavailability
         2. Amatoxins inhibit RNA polymerase II and suppress protein synthesis
      2. Amanita phalloides (severe hepatotoxicity)
         1. White cap and white gills
         2. Stem ascends from a cup at the base of the mushroom
         3. Stem encircled by a white skirt below the cap
      3. Amanita Virosa
      4. Amanita Verna
      5. Galerina Species
      6. Lepiota Species
   3. Nephrotoxic mushrooms
      1. Norleucine mushrooms (includes Amanita smithiana)
      2. Orellanine mushrooms
3. Findings: Hepatotoxic mushrooms (Cyclopeptide Mushrooms, Amatoxins)
   1. Phase 1: Gastrointestinal (5-24 hours after ingestion)
      1. Diarrhea
      2. Nausea
      3. Vomiting
   2. Phase 2: Liver Injury (12-36 hours after ingestion)
      1. Increased Liver Function Tests
      2. Increased INR
   3. Phase 3: Liver Failure (2-6 days after ingestion)
      1. Hypoglycemia
      2. Jaundice
      3. Renal Failure
      4. Hepatic Encephalopathy and coma
4. Management: Approach
   1. See Unknown Ingestion
   2. Call poison control for any suspected ingestion
      1. Consulting mycologists may be available in some regions if mushroom ingested is brought to ED
   3. Initial general management
      1. Intravenous hydration and Anti-emetics are typically the only management needed
      2. Decontamination if recent ingestion
         1. Oral Activated Charcoal may absorb amatoxins
   4. Symptom presentation may be more accurate than mushroom identification
      1. Vomiting within 1-2 hours of ingesting a single mushroom
         1. Gastrointestinal irritation is more likely
         2. Intravenous hydration and Anti-emetics are typically the only management needed
      2. Vomiting with later onset may suggest hepatotoxic mushroom ingestion
         1. See Hepatotoxic mushroom ingestion
         2. Liver Transaminases (AST, ALT) are typically increased by the onset of gastrointestinal symptoms
   5. Hepatotoxic mushroom ingestion suspected
      1. Admit all patients
      2. Obtain baseline Liver Function Tests and follow serial levels
      3. First-line management
         1. N-Acetylcysteine
      4. Additional management
         1. High dose Penicillin (Benzylpenicillin) 0.5 to 1.0 MU/kg/day IV
         2. Cimetidine
      5. Other medications used
         1. Silymarin (Milk Thistle extract)
         2. Thioctic Acid
      6. Consider for liver transplant
         1. Indicated in acute toxic fulminant liver failure
   6. Nephrotoxic mushrooms
      1. Present with Acute Renal Failure starting 2-5 days after ingestion (presentation may be delayed 2 weeks)
      2. May require Dialysis
         1. Renal Function returns in most cases
   7. Hallucinogenic mushooms
      1. Supportive care
      2. Resolves without residua
   8. Cholinergic mushrooms
      1. See Cholinergic Toxicity
      2. Muscarinic effects (Excessive Salivation, eye tearing, Diarrhea)
      3. Typically do not cause nicotinic effects (paralysis or Seizures)
5. References
   1. Swadron and Nordt in Majoewsky (2013) EM:Rap 13(3):2
   2. Tomaszewski (2021) Crit Dec Emerg Med 35(3):24