Case study: Australian mushroom poisoning

On 29 July 2023, Erin Patterson hosted a luncheon at her residence in Victoria. Her four guests were aged between 60 and 70 years and fell ill shortly after the meal. Three of the four guests died within a week of the lunch. The only survivor spent months in hospital in a coma and was finally released in September.

The symptoms were said to be consistent with that of death cap mushroom poisoning. This is one of the deadliest mushroom varieties found in certain parts of Australia, including Victoria.

Death cap dinner?

Amanita phalloides, commonly known as death cap mushroom, contains cytotoxins, specifically amatoxins and phallotoxins. After ingestion, signs of gastrointestinal distress arise first, followed by liver and kidney damage. If a large enough amount is ingested death can invariably occur. Death cap mushrooms are responsible for 90% of deaths relating to mushroom consumption.

Many individuals fall ill by ingesting poisonous mushrooms mistaking them for 'magic' mushrooms (hallucinogenic mushrooms).

Misidentification of mushrooms can also cause accidental fatalities.

Mushroom pickers often go out in search of exotic mushrooms and may mistake poisonous mushrooms for edible ones.

Impact on vital organs

The main target organ of toxicity is the liver, although other organs are also affected, especially the kidneys.

Many antidotes have been tried and tested but none are fully effective in counteracting the mushroom poison. The cornerstone treatment for those with Amanita phalloides poisoning and in fulminant hepatic failure remains liver transplant.

Poisoning allegations

Erin Patterson was arrested on three counts of murder and five counts of attempted murder. The three murder counts, and four attempted murder counts relate to incidents of allegedly poisoning of her ex-husband Simon Patterson in 2021 and 2022 while the fifth count relates to Ian Patterson who was present at the lunch.

Erin Patterson remains firm in her explanation that she purchased button mushrooms from her local supermarket as well as dried mushrooms purchased from an Asian grocery store in Melbourne months before.

She also explains that she ate the food, fell ill along with the others and went to hospital, then felt better after she was given a liver-protecting drug.

The case is ongoing and will be back in court in May 2024.