The Poison Review

Ingestion of a newly described North American mushroom species from Michigan resulting in chronic renal failure: Cortinarius orellanosus. Judge BS et al. Clin Toxicol 2010 Jul 8. [Epub ahead of print]

Abstract

The authors describe the development of chronic renal failure in a 53-year-old woman who ingested mushrooms she had picked herself under an oak tree in western Michigan.  At three days after ingestion she developed gastrointestinal symptoms, and at nine days stopped producing urine.  Serum creatinine was 18.3 mg/dL, and she was admitted to hospital for hemodialysis.

A specimen of the mushroom ingested underwent genetic analysis and was found to be similar — but not identical — to the “Fool’s webcap Cortinarius orellanus (pictured). The authors call this new species C. orelslanosus.

The clinical features of this case are typical of orellanine poisoning: a latent period of several days between ingestion and the onset of gastrointestinal symptoms, then progression of decreased urine output leading to anuria over a number of days.  The renal failure can be persistent — one year after presentation, the patient described here was still on peritoneal dialysis.

Cultural note: In 2008, Nicholas Evans — the author of The Horse Whisperer — along with several friends and family members were poisoned after eating the Deadly Webcap mushroom (C. speciosissimus) and had to undergo hemodialysis.  These Lethal Webcap mushrooms can be confused with chanterelles and other edible species, or even hallucinogenic little brown mushrooms.

Another nephrotoxic species found in North America is Amanita smithiana. The clinical toxicity of this mushroom is similar to that associated with the Lethal Webcaps, except for the much more rapid onset of gastrointestinal manifestations.