The initial symptoms of a new multisystem disease probably caused by ingestion of denatured rapeseed oil were acute pleuropneumopathy, fever, headache, exanthems, myalgia, and eosinophilia. Later features were severe myalgia and thromboembolic accidents. The present phase of the illness is typified by scleroderma-like involvement, pulmonary arterial hypertension, and a neuromuscular syndrome. Nearly all the patients with these late changes are women. The pathological lesion is a peculiar form of non-necrotising vasculitis which primarily affects the intima.