Mushroom toxicity

Background

1. Two categories:
   1. Early-Onset Poisoning
      1. Toxicity begins within 2hr of ingestion; clinical course is usually benign
   2. Late-Onset Poisoning
      1. Toxicity begins 6hr after ingestion; clinical course is often serious/ possibly fatal

Early-Onset Poisoning

• Comprises majority of mushroom-induced intoxications

Clinical Features

1. Depends on the type of mushroom ingested
2. GI
   1. Nausea/vomiting/diarrhea
   2. Resolves within 24hr
3. CNS
   1. Euphoria, hallucinations
   2. Lasts 4-6hr
4. Muscarinic
   1. SLUDGE symptoms
   2. Diaphoresis, muscle fasciculations, miosis, bradycardia, bronchorrhea
   3. Resolves in 4-12hr

Treatment

1. GI predominant symptoms:
   1. Activated charcoal 0.5-1gm/kg
   2. Do not give antidiarrheal meds
2. CNS predominant symptoms:
   1. Place in dark, quiet room
   2. Benzos may be given to pts who are agitated
3. Muscarinic predominant symptoms:
   1. Consider atropine for severe symptoms; 0.5-1mg IV for adults; 0.01mg/kg IV for peds

Disposition

1. Discharge once symptoms have subsided

Delayed-Onset Poisoning

• Amanita species causes 95% of deaths
  • Toxin inhibits formation of mRNA and is heat stable

Amanita phalloides

Clinical Findings

• Stage 1 (GI)
  • Occurs 6-24hr after ingestion and lasts 12-24hr
  • The later the onset of symptoms the better the outcome
  • GI predominant symptoms:
    • Abd pain, vomiting and diarrhea (which may become bloody)
• Stage 2 (convalescent)
  • Occurs 48hr after ingestion and lasts 12-24hr
  • Symptoms subside and pt appears better
  • Liver deteriorates silently and precipitously (LFTs begin to rise)
• Stage 3 (failure)
  • Occurs 2-4d after ingestion
  • Fulminant liver failure
    • Hyperbilirubinemia, coagulopathy, hepatic encephalopathy, hepatorenal syndrome

Treatment

• Immediate therapy
  • Activated charcoal
    • Some advocate repeated doses during the first 24hr
      • Amatoxin undergoes enterohepatic circulation
  • Penicillin
    • High doses 1 mil units/kg/d effective in animal studies (inhibits amatoxin uptake)
  • Silibinin (milk thistle)
    • Free radical scavenger used successfully in Europe; 25-50mg/kg/d
• Ongoing therapy
  • Glucose monitoring
    • Hypoglycemia is one of the most common causes of death in early mushroom toxicity
  • Liver/renal failure monitoring
    • Serial LFTs, chem, coags
  • Prepare for liver transplant
    • Progressive coagulopathy, encephalopathy, renal failure are indications for transplant

Disposition

• Admit all pts suspected of ingesting amatoxin containing mushrooms for at least 48hr

Gyromitra mushrooms

• also known as "brain fungi"
• inhibits formation of Vitamin B6 and BAGA

Clinical findings

• GI upset, fatigue, muscle cramps
• Can present with refractory seizures

Treatment

• Supportive care
• High dose pyridoxine for refractory seizures (5g IV initially)

Crotinarius mushrooms

• contain toxin Orellanine

Clinical findings

• Headache, chills, malaise, nausea and vomiting over days
• Can see delayed renal failure 1-3 weeks after exposure

Treatment

• Supportive
• If renal failure from mushroom exposure, recovery can take several weeks. May need temporary hemodialysis.

Source

Tintinalli