[Prion diseases in men].

Since the outbreak of "mad cow disease" and, more recently, the occurrence of cases of iatrogenic Creutzfeldt-Jakob disease in children who received pituitary extracts, there has been increasing public awareness and concern regarding the spongiform encephalopathies. These disorders appear to be caused by an extraordinary agent, unlike any previously described, called a "prion". All are progressive dementing diseases which are not associated with any specific immune or inflammatory response. At present there is no effective treatment.