Orellanine poisoning: rapid detection of the fungal toxin in renal biopsy material.

Background: Mushroom poisoning by some species of the Cortinarius (Agaricales) often lead to irreversible renal failure caused by the nephrotoxin orellanine. In 1994 and 1995, six poisoning outbreaks involving ten individuals in Northern Italy and in Austria were investigated.
Methods: A total of 87 clinical samples (urine and blood samples including renal biopsy material of three patients) were examined for the presence of orellanine by thin layer chromatography.
Results: Orellanine can be detected after a relatively long period following poisoning by performing a simple thin layer chromatography technique using small quantities of renal biopsy material. No toxin was found in urine or blood samples.
Conclusions: Orellanine is rapidly concentrated in the kidneys in a relatively soluble form and cannot be detected in urine, blood and dialysis fluids at the time when first symptoms appear.