Mushroom Poisoning


Mushroom Poisoning, Cyclopeptide Mushroom, Hepatotoxic Mushroom, Neurotoxic Mushroom, Nephrotoxic Mushroom, Amanita Species Mushroom Poisoning, Toadstool Poisoning, Mycotoxins, Mushroom Ingestion

  • Epidemiology
  1. Prepared foods with toxic mushrooms is most common type of lethal exposure
  2. Mushroom Ingestions are responsible for 50% of U.S. plant and fungal ingestion related deaths
  • 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
    6. Morel (Morchella) mushrooms (when raw or undercooked)
      1. See Morel Mushroom Poisoning
  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
  • 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
  • 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 (early versus delayed effects) 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
  • Management
  • Early Onset Mushroom Poisoning
  1. Background
    1. Presents with symptoms (often starting with Nausea and Vomiting) in first 6 hours after ingestion
    2. Prognosis is better with early onset symptoms (than delayed onset)
    3. Supportive care (Intravenous Fluids, Antiemetics)
  2. Hallucinogenic mushooms (e.g. Psilocybin containing mushrooms)
    1. Supportive care
    2. Resolves without residua
  3. Cholinergic mushrooms
    1. See Cholinergic Toxicity
    2. Muscarinic effects (Excessive Salivation, sweating, eye tearing, Diarrhea, colic, Pulmonary Edema)
    3. Typically do not cause nicotinic effects (paralysis or Seizures)
    4. Consider Atropine
  • Management
  • Delayed Onset Mushroom Poisoning
  1. Background
    1. Presents with symptoms starting >6 hours after ingestion
    2. Delayed onset mushroom toxicity is responsible for 90% of mushroom related deaths
    3. Early and repeat dosing of Activated Charcoal may reduce mushroom absorption and enterohepatic recirculation
    4. Early Consultation with poison control and hepatology (or nephrology as needed)
  2. Hepatotoxic Mushroom ingestion suspected
    1. Example: Amanita phalloides (death cap mushroom)
      1. Most lethal mushroom (significant ingestion is fatal without Liver Transplant)
      2. Contains phallotoxin, responsible for gastrointestinal distress
      3. Contains amatoxin responsible for hepatic necrosis and renal tubular necrosis
      4. Begins with gastrointestinal distress and may progress to fulminant hepatic failure within first 24 hours
    2. Admit all patients (preferably to a Liver Transplant capable center)
    3. Obtain baseline Liver Function Tests and follow serial levels
    4. First-line management
      1. N-Acetylcysteine
    5. Additional management
      1. High dose Penicillin (Benzylpenicillin) 0.5 to 1.0 MU/kg/day IV
      2. Cimetidine
    6. Other medications used
      1. Silymarin (Milk Thistle extract)
      2. Thioctic Acid
    7. Consider for Liver Transplant
      1. Indicated in acute toxic fulminant liver failure
  3. Nephrotoxic Mushrooms
    1. Example: Amanita smithiana
      1. May progress to Renal Failure in first 1-2 days
    2. Present with Acute Renal Failure starting 2-5 days after ingestion (presentation may be delayed 2 weeks)
    3. May require Dialysis
      1. Renal Function returns in most cases
  • References
  1. Swadron and Nordt in Herbert (2013) EM:Rap 13(3):2
  2. Tagliaferro (2023) Crit Dec Emerg Med 37(1): 21-9
  3. Tomaszewski (2021) Crit Dec Emerg Med 35(3):24