Viral complications after transplantation

All hospital patients are at risk of acquiring infections from visitors or staff members or by nosocomial transmission. Transplant patients have additional routes of acquisition which together represent the major source of infection. These are: reactivation of latent virus; transmission with the donor organ; and transmission by blood. A wide variety of viruses have been implicated, with the common feature that they establish either chronic or latent infection in the donor or recipient. The aim of this paper is to review the natural history, clinical features, diagnosis, prevention and treatment of each of these viral infections. A basic principle will be that the presence of specific antibodies in a donor or recipient before undergoing transplantation is a marker of latent virus within that individual. After transplantation, patients have impaired immune responses, thereby rendering serology unreliable for diagnostic purposes. Instead, methods which detect the virus directly in clinical material should be used.