Acute Gastroenteritis Most common manifestation of toxic mushroom ingestion Onset of abdominal cramping, diarrhea, and vomiting within 2 hours of ingestion Self-limited, usually resolving in 12 hours (although wide variability in responses exist) Treatment is supportive with po or iv rehydration

Early Gastroenteritis Even the common supermarket mushroom can induce an acute gastroenteritis in susceptible individuals Agaricus bisporus (supermarket mushroom)

Early Gastroenteritis Chloropyllum molybdites (Green-spored parasol) Common mushroom found in eastern and southern North America (especially in lawns)

Early Gastroenteritis Omphalotus olearius (Jack-o-Lantern Mushroom) Luminescent, orange- yellow mushroom found in clusters at base or stumps of deciduous trees

Delayed Gastroenteritis Amanita phalloides (Death cap mushroom) Accounts for 95% of deaths due to mushroom ingestion White, smooth cap, with white gills, not attached to the stalk. Stalk is white, cottony to somewhat pearly, sometimes with a bulbous base. White, large, flaring annulus (ring) is located at the top of the stalk; and cup-like sheath (volva) is found at the base of the stalk. The spores are white. Heat stable amatoxin binds to RNA polymerase II in hepatocytes and induces liver necrosis

Delayed Gastroenteritis Amanita phalloides (Death cap mushroom) 3 stages of poisoning Acute gastroenteritis with profuse, cholera-like diarrhea, starting 5-12 hours after ingestion Latent period lasting 2-3 days with ongoing liver damage but symptomatic improvement Clnically apparent hepatic and renal failure Treatment For recent ingestion, gastric lavage (< 1 hour) or activated charcoal (< 24 hours) Volume resuscitation, repletion of electrolytes and glucose High dose PCN Silibinin (milk thistle extract) Charcoal hemoperfusion Transplant

Delayed Gastroenteritis Gyromitra esculenta (false morel) Gyromitrin toxin is converted to monomethylhydrazine, a form of rocket fuel, that has CNS, liver, and renal toxicities Clinical presentation Onset of abdominal pain, vomiting, diarrhea at 6-10 hours after ingestion Closely followed by CNS syptoms of weakness, dizziness, headache, confusion, and possibly seizures May resolve or progress to liver and renal failure Hemolysis and methemoglobinemia are reported Treatment Gastric lavage or charcoal if recent ingestion Aggressive rehydration High dose pyridoxine for CNS toxicity Methylene blue for methemoglobinemia

CNS Syndromes Psylocybe family Psilocybin inhibits serotonin activity Clinical presentation Acute onset (15-30 minutes of ingestion) of symptoms ranging from mild euphoria to frank hallucinosis Treatment is primarily supportive