History and admission findings: A 44-year-old male and his 40-year-old wife, both previously in good health, were admitted for abdominal pain, diarrhea, vomiting, severe headache, and oliguria after ingestion of wild mushrooms two weeks earlier. Physical examination revealed costo-vertebral-angular tenderness in the husband and abdominal tenderness in both patients.
Investigations: Laboratory showed acute renal injury with markedly increased serum concentrations of creatine and urea. On abdominal ultrasound, the kidneys were slightly increased in size with echogenic parenchyma and prominent medullary pyramids. Signs of an immunological or infectious etiology were missing. Histological investigation of the renal biopsy showed acute interstitial nephritis with marked tubular damage in both cases.
Diagnosis, treatment and course: History and histological findings were consistent with Orellanus syndrome following ingestion of mushrooms of the Cortinarius species. In both patients, haemodialysis was initiated. In the husband, dialysis was discontinued on day 8 and a follow-up visit after one month revealed stage 5 chronic kidney disease. In the wife, continuation of haemodialysis in an ambulatory setting required implantation of a temporary vascular catheter.
Conclusions: In cases of acute renal injury of unknown origin, ingestion of mushrooms of the Cortinarius species should be included in the differential diagnoses. In particular, initial gastrointestinal complaints may point to this rare differential diagnosis.