History and clinical findings: A 26-year-old woman with no contributory medical history became anuric after several days of nausea and vomiting. She was admitted to our hospital with suspected acute renal failure.
Investigations: Laboratory tests revealed greatly elevated BUN and creatinine. There was no evidence of postrenal obstruction, infection or systemic disease. Kidney biopsy showed interstitial nephritis.
Diagnosis, therapy and clinical course: Further questioning revealed poisoning with a nephrotoxic mushroom of the genus Cortinarius, which the patient had eaten together with her husband nine days before admission. The patient's husband developed anuric renal failure, too, and was admitted to our hospital. Hemodialysis was instituted on day 1. More than one year later, both patients remain on chronic dialysis.
Conclusions: Intoxication with mushrooms of the genus Cortinarius should be considered in the differential diagnosis of otherwise unexplained acute renal failure, especially in autumn and late summer. These mushrooms can cause an interstitial nephritis. Once dialysis has to be instituted the prognosis is rather poor: 50 % of these patients develop chronic renal failure. So far there is no causative therapy. In case of chronic renal failure, kidney transplantation is possible.