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Mushroom Toxicosis 667

Mushroom Toxicosis Client Education
Sheet
VetBooks.ir Diseases and Disorders

• Isoxazole: acute inebriation followed by coma;
BASIC INFORMATION
mate receptors triggering CNS stimulation;
generally self-limited mental dullness; ibotenic acid acts on gluta-
Definition combined effects result in hyperesthesia,
Condition resulting from ingestion of any of HISTORY, CHIEF COMPLAINT sedation, intermittent agitation
a variety of toxic mushrooms; toxic syndrome • History of exposure; mushrooms in the
produced depends on mushroom type and vomitus DIAGNOSIS
amount ingested: • GI: vomiting, diarrhea within 4 hours of
• Gastrointestinal (GI) irritant mushrooms: ingestion Diagnostic Overview
large variety of species • Hallucinogenic: dysphoria, vocalization in Diagnosis is reached when nonspecific disorders
• Hallucinogenic mushrooms: Psilocybe spp, 30 minutes to 4 hours of ingestion (e.g., gastroenteritis, hepatotoxicity, neurologic
Panaeolus spp • Hepatotoxic: acute, severe vomiting ± diar- disturbance) are combined with evidence of
• Hepatotoxic mushrooms: Amanita spp, rhea in 8-24 hours; apparent recovery, then exposure, such as mushrooms in vomitus. There
Galerina spp, Lepiota spp return of GI signs; evidence of acute liver is no practical clinical confirmatory test.
• Nephrotoxic mushrooms: Cortinarius spp failure in 24-72 hours; acute kidney injury
• Muscarinic mushrooms: Inocybe spp, Clitocybe possible in severe cases Differential Diagnosis
spp • Nephrotoxic: acute kidney injury 12 • GI, muscarinic: parvoviral enteritis, foreign
• Gyromitrin mushrooms: Gyromitra spp, hours to 8 days after exposure, polyuria, body, garbage toxicosis, organophosphate and
Helvella crispa, Helvella lacunosa polydipsia carbamate pesticide toxicosis
• Isoxazole mushrooms: Amanita gemmata, • Muscarinic: salivation, vomiting, diarrhea, • Hepatotoxic: other toxicoses (acetaminophen,
Amanita muscaria, Amanita smithiana, Amanita lacrimation, bradycardia within 4 hours of iron, blue-green algae, Cycas spp), infectious
strobiliformis, and Tricholoma muscarium ingestion hepatitis
• Gyromitrin: GI signs in 6-8 hours, hepatore- • Nephrotoxic: ethylene glycol, grapes/raisins,
Epidemiology nal and hemolytic syndrome 36-48 hours nonsteroidal antiinflammatory drug (NSAID)
SPECIES, AGE, SEX after ingestion toxicity, leptospirosis
All mammalian species are susceptible; dogs • Isoxazole: vomiting, ataxia, disorientation, • Isoxazole, hallucinogenic: encephalitis,
more likely to ingest than cats sleep/coma within 4 hours of ingestion portosystemic shunt, serotonergic drugs,
cannabis, other illicit substances
GEOGRAPHY AND SEASONALITY PHYSICAL EXAM FINDINGS
• Highest incidence of mushroom poisoning • GI: vomiting, diarrhea, dehydration possible, Initial Database
(all types) occurs from August to October. but generally unremarkable • CBC, serum biochemistry profile, urinalysis,
• GI irritant mushrooms: wide distribution; • Hallucinogenic: vocalization, agitation venous or arterial blood gas measurement:
long range of fruiting seasons • Hepatotoxic: signs of abdominal pain, icterus, depends on type. Marked increase in liver
• Hallucinogenic mushrooms: wide distribu- hypotension, hepatomegaly, coma enzymes ± bilirubin; azotemia; hypoglycemia;
tion; Pacific Northwest and Gulf Coast; • Nephrotoxic: uremic signs (p. 23) acidosis
lawns, gardens, roadsides, open woods; • Muscarinic: vomiting, hypersalivation, • Coagulation profile: coagulopathy with
cultivated in homes for recreational use lacrimation, diarrhea, bradycardia, wet lung severe liver injury; disseminated intravascular
• Hepatotoxic mushrooms: wide distribution sounds coagulation (hepatotoxic mushrooms)
throughout United States; wide variation in • Gyromitrin: vomiting, abdominal pain, • Rule out differential diagnosis depending on
habitats and fruiting seasons icterus, hepatomegaly, hemoglobinuria, presentation (e.g., leptospirosis serology)
• Nephrotoxic mushrooms: common in North anemia
America, especially Canada; grows in woods • Isoxazole: agitation, tremors, disorientation, Advanced or Confirmatory Testing
and forests; uncommon in urban areas GI signs • Abdominal imaging: hepatomegaly (hepa-
• Muscarinic mushrooms: wide distribution; totoxic mushrooms)
forests or fields; fruits in fall, early winter in Etiology and Pathophysiology • Liver biopsy (hepatotoxic): liver necrosis
temperate areas, year-round in warm, moist • GI: several mechanisms; hypersensitivity, • Urine: amatoxins can be detected in the urine
climates local irritation as early as 90-120 minutes after ingestion
• Gyromitrin mushrooms: throughout North • Hallucinogenic: stimulate serotonin and of an amatoxin-containing mushroom.
America, primarily in the spring possibly norepinephrine receptors in central • Urine: muscimol can be detected in urine;
• Isoxazole mushrooms: eastern United States and peripheral nervous systems turnaround time is long and little value in
and Pacific Northwest; forests; fruits in • Hepatotoxic: cyclopeptides interfere with acute cases
spring/early summer and again in fall DNA synthesis, protein synthesis, resulting
in cellular necrosis TREATMENT
Clinical Presentation • Nephrotoxic: orellanine causes energy
DISEASE FORMS/SUBTYPES depletion and tubulointerstitial nephritis; Treatment Overview
• GI: acute, self-limited GI distress cortinarin causes oxidative membrane injury Initially, manage potentially life-threatening
• Hallucinogenic: acute central nervous system • Muscarinic: bind muscarinic acetylcholine abnormalities (e.g., seizures, hypoglycemia,
(CNS) signs; generally self-limited receptors in parasympathetic nervous system; bleeding disorders). Further treatment con-
• Hepatotoxic: acute GI signs, then liver failure prolonged duration due to lack of degrada- sists of decontamination and supportive care:
in 24-72 hours tion; does not inhibit acetylcholinesterase induction of vomiting and administration of
• Nephrotoxic: renal tubular dysfunction • Gyromitrin: metabolized to monomethyl- activated charcoal to minimize absorption and
• Muscarinic: acute muscarinic signs hydrazine, leading to metabolic alterations treatment to minimize hepatic/renal injury,
• Gyromitrin: GI signs followed by neurologic, • Isoxazole: muscimol mimics gamma- excessive muscarinic effects, and complications
hepatorenal, and/or hemolytic syndromes aminobutyric acid (GABA), causing sedation, as they arise.

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