Mushroom toxicity

Background

• Onset of diarrhea <8hr after ingestion is sensitive marker for fatality

Stages

• First stage (6-24hr after ingestion)
  • Abd pain, fever, N/V, diarrhea, tachycardia, hyperglycemia, hypotension
• Second stage (48hr after ingestion)
  • Symptoms subside (even though liver deteriorates precipitously)
• Third stage
  • Fulminant liver failure

Amatoxin

- inhibits rna polymerase and interfers c dna rna transcriptn. -

- Disruption of protein synthesis causes fatal intestinal hepatic renal dz.

- Is heat stable- not affected by cooking

- delayed tox- 6-24 hrs

- liver and kidney failure

Gyromitrins

- oxidizes hemoglobin- can cause methemoglobinemia

- inhibits glutamic acid decarboxylase- leads to low GABA level - neuro sxs

-delayed 6-8 hrs -

- hepatitis

- cns changes

- hemolysis

- metHb

Orellanine and orelline

Coprine

- if ingested c etoh can lead to Beta adrenergic stimulation like disulfiram rxn

Ibotenic acid and muscimol

- anticholinergic activity and hallucinatns,

Muscarine

- cholinergic stimulatn- blurred vision, sweating, HA, lacrimation, salivation, urinary freq

Psilocybin and psilocin

- nv, hallucination, flashbacks

Diagnosis

- if > 6h from ingestion to sxs suggests amatoxin, gyromitrin, orellenine, oreline. Do LFT, PT

- if < 3h is ibotenic acid, muscimol, muscarine, psilocin

- temporal assoc c etoh and sxs suggest coprine poisoning

Treatment

- charcoal

- no antiemetic or imodium since will cause increased toxin absorption

- golightly whole bowel irrigation

- if amatoxn, gyromitrin, orellanine admit for observatn

TOXIN SPECIFIC TX-

Amatoxn-

- forced diuresis

- charcoal hemoperfusion

- high dose penicilin- inhibits amatoxn uptake by hepatocytes. One million units/kg in divided doses per day for 2- 3 days. Sz is complicatn.

- high dose cimetidine- inhibits P450 enzyme. 2 gms q 4h iv

- liver xplant

- hyperbaric O2

- high dose ascorbic acid

- N- acetylcysteine

Gyromitrin poisoning-

- pyridoxin 25mg/kg iv over 30min. Repeat up to 4 times in 24 hrs if sxs persist.

- benzos

- diuresis

- blood xfusion

- methylene blue

Orellanine

- fluids

Coprine- etoh

- dopamine for hypotn

Ibotenil- muscimol

- control neuromuscular hyperactivity- benzos. Consider physostigmine if refractory agitation and tachy and perif anticholinergic findings

Muscarine poisoning

- atropine

- albuterol

- anti histamines,

Source

6/06 MISTRY