Amatoxins

Epidemiology

• 35 mushroom species across three genera (Amanita, Galerina, Lepiota)

• Contain Amatoxin

• About 50 deaths per year in Europe and Asia

• Serious toxicity occurs by foraging and eating the misidentified mushrooms

• Boiling and cooking DOES NOT remove the Amatoxin

• Kids rarely affected due to limited toxins in small amount of mushroom they might ingest

Amatoxin-Containing Mushrooms

• Amanita

  • Commonly involved

  • Names include Death cap, death cup, destroying angel, and fool’s mushroom

  • Have no offensive taste or odor

  • Typically grow as a single mushroom in moist forests

• Lepiota and Galerina less common

Pathophysiology

• Contains fun sounding substances like amatoxins, virotoxins and the ominous sounding phallotoxin

• Amatoxins are heat stable

• Absorbed in gut, transported to liver and uptake into hepatocytes

• Once in a cell, stopped protein synthesis and cause call death

Symptoms

• Delayed symptoms more than 6 to 12 hours after consumption = potentially serious ingestion

• Three phases

  • Phase 1: Dyssentry (6 to 24 hours post-ingestion)

    • Abdominal pain

    • Vomitting

    • Severe diarrhoea with blood and mucous

    • Haematuria

    • Shock

  • Phase 2: Apparent Recovery (24 to 36 hours post-ingestion)

    • Gradually resolution of dyssentry

    • However liver enzyme elevations peak at 60 to 72 hours post-ingestion

  • Phase 3: Fulminant hepatic and multisystem organic failure (48 to 96 hours post-ingestion)

    • Massive liver cell death

    • Liver blood vessel flow is disrupted

    • Nephrotoxin effects on kidney

    • Pancreatitis

Diagnosis

• Unwell with a history of eating random forest mushrooms

• Urine Amatoxin levels

Management

• Supportive care

  • Liver toxicity

    • Treat low blood glucose

    • Treat high ammonia with lactulose

    • Vitamin K and fresh frozen plasma for blood clotting

• Gut decontamination

  • Activated charcoal (AC)

  • No benefit to gastric emptying or lavage

• Elimination enhancement

  • Multidose Activated Charcoal (MDAC) every 4 hours

• Amatoxin uptake inhibitors

  • Silibinin dihemisuccinate

• Antioxidant Therapy

  • NAC recommended

  • Cimetidine: 300 mg IV every 8 hours until clinical improvement

  • Vitamin C: 3 g IV daily until clinical improvement

• Liver Transplant

Mortality rates

• Previously up to 50% in older cases

• Currently 10% with modern medicine

Resources

• Amatoxin-containing mushrooms - up To Date