Mushroom Poisoning

Author:

Michael E.Nelson

Timothy B.Erickson

Description

Amanitin/phalloidin:
- Species:
  - Amanita phalloides (“death cap”)
  - Amanita virosa/Amanita verna (“destroying angel”)
  - Galerina marginata, Galerina venenata
- Mechanism:
  - Cyclopeptide toxins inhibit RNA polymerase 2, which kills GI epithelium, hepatocytes, nephrocytes
Gyromitrin:
- Species:
  - Gyromitra esculenta (“false morels”)
  - Other Gyromitra spp.
- Mechanism:
  - Gyromitrin hydrolyzed to monomethylhydrazine
  - Inhibits pyridoxal phosphate
  - Results in decreased GABA production
  - Damage to RBCs, hepatocytes, neurons
Muscarine:
- Species:
  - Inocybe (several species)
  - Clitocybe (several species)
  - Boletus sp.
  - Rubinoboletus sp.
- Mechanism:
  - Muscarine acts like acetylcholine resulting in parasympathomimetic symptoms
Coprine:
- Species:
  - Coprinus atramentarius (“inky caps”)
- Mechanism:
  - Blocks acetaldehyde dehydrogenase
  - Causes disulfiram-like reaction if mixed with alcohol
Ibotenic acid/muscimol:
- Species:
  - Amanita pantherina (“panther cap”)
  - Amanita muscaria (“fly agaric”)
  - Amanita ibotengutake (Japanese Ringed-Bulb)
- Mechanism:
  - Ibotenic acid is derivative of glutamate
  - Muscimol is GABA derivative
Psilocin/psilocybin:
- Species:
  - Psilocybe and Panaeolus spp. as well as others
  - Stalks may turn blue upon hand ling, nonspecific
- Mechanism:
  - Similar structure to lysergic acid diethylamide, effect serotonin receptor
Gastric irritants:
- Many various mushrooms, including those normally considered edible
Orellanine:
- Species:
  - Cortinarius (several species)
- Mechanism:
  - Direct renal toxicity
Neurovascular toxins
- Species:
  - Clitocybe amoenolens (Poison Dwarf Bamboo mushroom)
  - Clitocybe acromelalgia
- Mechanism:
  - Acromelic acids A-E, Kainate analogs, peripheral glutamate receptors
Myotoxin
- Species:
  - Tricholoma equestre (Yellow Knight, “man on horse”)
- Mechanism unknown, induces rhabdomyolysis

Diagnosis ⬆ ⬇

[Section Outline]

Signs and Symptoms
Essential Workup
Diagnostic Tests & Interpretation
Differential Diagnosis

Signs and Symptoms

Amanitin/phalloidin:
- Nausea
- Vomiting
- Abdominal cramps
- Bloody diarrhea
- Clinical course:
  - Onset of symptoms delayed 6-36 hr with development of GI symptoms
  - Transient latent phase may last 2 d (no pain/symptoms)
  - Can progress to hepatic or renal failure and death in 2-6 d
  - Most lethal mushroom toxins
Gyromitrin:
- 1st 5-10 hr:
  - Abdominal cramps
  - Nausea/vomiting
  - Watery diarrhea
- Later symptoms:
  - Weakness
  - Cyanosis
  - Confusion
  - Seizures
  - Coma
Muscarine:
- Cholinergic symptoms include:
  - Miosis
  - Salivation
  - Lacrimation
  - Sweating
  - Diarrhea
  - Flushed skin
  - Nausea
  - Bradycardia
  - Bronchoconstriction
- Onset usually within 1 hr (may be delayed)
Coprine:
- Disulfiram-like reaction within minutes to hours when combined with alcohol:
  - Flushing
  - Sweating
  - Nausea/vomiting
  - Palpitations
Ibotenic acid/muscimol:
- Relatively rapid onset of 30-120 min
- GABA agonist effects include:
  - Hallucinations
  - Dysarthria
  - Ataxia
  - Somnolence/coma
- Glutamatergic effects (mainly pediatrics):
  - Seizures
  - Hyperkinetic behavior
  - Muscle cramps/myoclonic movements
Psilocin/psilocybin:
- Rapid onset, usually resolves in 6-12 hr
- Visual hallucinations
- Alteration of perception
- Mydriasis
- Tachycardia
- Fever and seizures in children
Gastric irritants:
- Group of toxins that cause nausea, vomiting, intestinal cramps, and watery diarrhea
- Onset 30 min-3 hr, usually resolved in 6-12 hr
Orellanine/Amanita smithiana:
- Nausea/vomiting
- Headache
- Sweating
- Chills
- Low-back pain
- Polydipsia
- Clinical course:
  - May progress to oliguria and acute renal failure
  - Markedly delayed onset of symptoms (2-14 d)
Neurovascular toxin
- Erythromelalgia: Erythema, swelling, pain of distal extremities
- Clinical course:
  - Onset of symptoms 24 hr after ingestion
  - Paresthesia of digits, burning pain
  - Red/swollen hand s and feet
  - Heat and dependent position worsen pain
  - Can last weeks to months
- Electromyogram: Polyneuropathy with sensory and motor fiber impairment
Myotoxin/T. equestre:
- Acute rhabdomyolysis:
  - Myalgias/arthralgias
  - Hematuria/dark urine
  - Decreased urine output
- Dehydration
- Myocarditis, arrhythmias

History

Time of ingestion
Time of symptom onset
Quantity ingested
Preparation: Raw or cooked
Picked in the wild or store-bought
Coingestants, other mushrooms
Alcohol/drug use history
Symptoms of family members, friends

Physical Exam

Vital signs
Changes in mental status
Pupillary response
Cardiopulmonary exam
Abdominal exam
Neurologic exam

Essential Workup

Mushroom description:
- Pileus (cap); margin shape
- Stipe (stem)
- Lamellae (gills)
- Veil
- Annulus (ring)
- Volva
Store mushroom in brown paper bag for future identification:
- <3% of cases result in an exact mushroom identification
- Digital photography and electronic image transfer to poison-control center or regional mycologist

Diagnostic Tests & Interpretation

Lab

CBC
Prothrombin time (PT), partial thromboplastin time (PTT)
Electrolytes, BUN, creatinine, glucose
Urinalysis
LFTs, creatine phosphokinase (CPK)
Imaging
Spore print: Mycologist needed for specific genus/species interpretation

Differential Diagnosis

Very broad differential
Gastroenteritis, viral vs. bacterial
Hepatitis/acetaminophenhepatotoxicity
Acute renal failure (many causes)
Rhabdomyolysis (many causes)
Cholinergic syndrome (e.g., organophosphates)
Anticholinergic syndrome
Seizures (many causes)
Vasculitis

Treatment ⬆ ⬇

[Section Outline]

Prehospital
Initial Stabilization/Therapy
ED Treatment/Procedures
Medication

Prehospital

Bring any unconsumed mushrooms or mushroom pieces to hospital to aid in diagnosis:

Refrigerate specimens if possible, place in brown paper bag

Initial Stabilization/Therapy

ABCs
Establish IV 0.9% NS
Monitor
Naloxone, D₅₀W (or Accu-Chek), and thiamine for altered mental status

ED Treatment/Procedures

General Measures

Decontamination:
- Activated charcoal (50-100 g)
- Gastric decontamination if early after ingestion and patient:
  - Has not yet vomited
  - Has normal mental and respiratory status
  - Is not undergoing hallucinations
Fluid rehydration and electrolyte replacement as necessary
Call local poison-control center at 800-222-1222 and request mycologist - digital picture may be electronically sent for identification
Obtain specimens (vomitus if needed) for identification

Mushroom-Specific Therapy

Amanitin/phalloidin:
- Administer activated charcoal PO q2-4h
- Hypoglycemia and elevated PT:
  - Signs of liver failure
  - Administer fresh-frozen plasma and vitamin K for coagulation disorders with active bleeding
- Administer calcium in presence of hypocalcemia
- Liver transplant for severe hepatic necrosis
- Consider N-acetylcysteine, high-dose penicillin G, or silibinin or polymyxin B if available (thioctic acid controversial)
Gyromitrin:
- Treat seizure with benzodiazepines, barbiturates, or propofol.
  - Administer pyridoxine (vitamin B₆) in severely symptomatic patients
- Treat liver dysfunctions similar to amanitin/phalloidin group
- Dialysis for renal failure
Muscarine:
- Administer atropine in severe cases
Coprine:
- Self-limited toxicity - supportive care
- Avoid syrup of ipecac (contains alcohol)
- β-Blockers for cardiac dysrhythmias
Ibotenic acid/muscimol:
- Usually self-limited toxicity
- Provide supportive care
- Monitor for hypotension
- Treat moderate symptoms with benzodiazepines, if severe anticholinergic symptoms; consider physostigmine
Psilocin/psilocybin:
- Self-limited toxicity
- Dark, quiet room and reassurance
- Benzodiazepines for agitation
- External cooling measures if needed in children
GI Irritants:
- When poisoning from above groups not suspected, administer fluids and antiemetics
- Provide supportive care
Orellanine and A. smithiana:
- Closely monitor BUN, creatinine, electrolytes, and urine output
- Forced diuresis with furosemide contraindicated
- Diuresis with alkalinization of urine with NaHCO₃ if signs of rhabdomyolysis
- Hemodialysis/renal transplantation may be needed
Neurovascular/Erythromelalgia:
- Place extremities affected in cold water
- Analgesics and supportive care
- Consider nicotinic acid (controversial)
Myotoxin/T. equestre:
- Fluid hydration
- Check and follow CPK
- Monitor urine output

Medication

Activated charcoal slurry: 1-2 g/kg up to 100 g PO
Atropine: 0.5 mg (peds: 0.02 mg/kg) IV; repeat 0.5-1 mg IV (peds: 0.04 mg/kg) q10min if secretions recur, to max. 1 mg/kg in children and 2 mg/kg in adults
Dextrose: D₅₀W 1 amp: 50 mL or 25 g (peds: D₂₅W 2-4 mL/kg) IV
Diazepam (benzodiazepine): 5-10 mg (peds: 0.2-0.5 mg/kg) IV
Lorazepam (benzodiazepine): 2-6 mg (peds: 0.03-0.05 mg/kg) IV
N-acetylcysteine: 150 mg/kg over 1 hr, then 12.5 mg/kg/hr for 4 hr then 6.25 mg/kg until hepatic injury resolves
Naloxone (Narcan): 0.04-2 mg (peds: 0.1 mg/kg) IV or IM initial dose
Nicotinic acid: 20-100 mg/day × 7 days, dose given over 1 hr IV; 100 mg/d orally over 3 mo with gradual taper
Physostigmine: 0.5-2 mg IM or IV in adults
Polymyxin B: 1.5-2.5 mg/kg/d in 2 doses administered as 1-hr IV infusions
Propranolol: 1 mg (peds: 0.01-0.1 mg/kg) IV
Pyridoxine: 70 mg/kg up to 5 g IV over 30 min
Silibinin: 5 mg/kg IV over 1 hr then 20 mg/kg/24 hr for 3 d
Thiamine (vitamin B₁): 100 mg (peds: 50 mg) IV or IM

Follow-Up ⬆ ⬇

[Section Outline]

Disposition
Follow-up Recommendations

Disposition

Admission Criteria

All symptomatic patients:
- Protracted vomiting, dehydration, liver or renal toxicity, or seizures
Transfer to tertiary medical center for early signs of renal or hepatic failure
Symptomatic infants and young children found with mushrooms:
- Assume ingestion
ICU admission for known ingestion of an amanitin-containing mushroom:
- Early liver service consultation

Discharge Criteria

Asymptomatic during 6-8 hr with 24 hr of close home observation and close follow-up (if reliable caregivers)

Issues for Referral

Potential liver or renal transplantation

Follow-up Recommendations

Drug detoxification programs if chronic recreational use

Pearls and Pitfalls ⬆ ⬇

There are old mushroom pickers, and bold mushroom pickers; but there are no old, bold mushroom pickers
Symptoms with late onset (>6 hr) generally indicate more lethal toxins
Lack of proper mycologic identification
Timely organ transplant referrals when indicated

Additional Reading ⬆ ⬇

DiazJH. Syndromic diagnosis and management of confirmed mushroom poisonings . Crit Care Med. 2005;33(2):427-436.
GarciaJ, CostaVM, CarvalhoAT, et al. A breakthrough on Amanita phalloides poisoning: An effective antidotal effect by polymyxin B . Arch Toxicol. 2015;89(12):2305-2323.
GoldfrankLR. Mushrooms. In: GoldfrankLR, ed. Goldfrank's Toxicologic Emergencies. 10th ed.New York: McGraw-Hill; 2015:1500-1514.
GraemeKA. Mycetism: A review of the recent literature . J Med Toxicol. 2014;10(2):173-189.
NakajimaN, UedaM, HigashiN, et al. Erythromelalgia associated with Clitocybe acromelalgia intoxication . Clin Toxicol. 2013;51(5):451-454.
TrabulusS, AltiparmakMR. Clinical features and outcome of patients with amatoxin-containing mushroom poisoning . Clin Toxicol. 2011;49(4):303-310.

section name header

Basics ⬇

Diagnosis ⬆ ⬇

History

Physical Exam

Lab

Treatment ⬆ ⬇

General Measures

Mushroom-Specific Therapy

Follow-Up ⬆ ⬇

Admission Criteria

Discharge Criteria

Issues for Referral

Pearls and Pitfalls ⬆ ⬇

Additional Reading ⬆ ⬇

Codes ⬆