A prion is a protein that is capable of self replication, thereby altering a cell's metabolism. It is responsible for a number of human and animal diseases (prionic diseases), all of which are always lethal. These diseases have enormous variability in their incubation periods, ranging from a few months to forty years. Prions accumulate and destroy nerve cells, causing spongiform encephalopathy. We discuss the clinical picture, epidemiology, and historical background of prionic diseases. The major focus of the discussion lies, however, on the theoretical possibility of iatrogenic transmission of prion infection due to topical formulations using ceramides (cerebrosides) or placenta of bovine origin, as well as the risk represented by some dermatological procedures such as skin grafts and collagen implants.
ceramides; dermatology; encephalopathy; prions
