Three cases of intoxication due to ingestion of Cortinarius orellanus are presented. The hallmark of the clinical picture is acute tubulo-interstitial nephritis appearing about 10 days after ingestion of the mushrooms. This time lag is specific for intoxication by Cortinarius orellanus. In all the three cases, acute gastroenteritic disorders and hepatocellular damage were observed initially and disappeared spontaneously. Histological examination reveals acute tubulointerstitial nephritis. Experimental data are discussed in regard to the clinical observations.