Cytomegalovirus and allograft failure after solid organ transplantation

Allograft rejection and infections are the two major complica­tions of solid organ transplantation. These clinical entities are intimately interrelated, with one predisposing to the other, in a bidirectional relationship. Allograft rejection and its treatment predisposes to various infections, most commonly with cytomegalovirus (CMV). In turn, the occurrence of CMV infection and disease increases the risk of developing acute rejection and chronic allograft dysfunction. In this chapter, we review the clinical and experimental data that support the association between CMV infection and chronic allograft loss after solid organ transplantation. The pathogenetic mechanisms that have been proposed, including immunologic cross-reactivity, the upregulation of immune molecules and the generation of adhesion molecules and inflammatory media­ tors are evaluated. The implications of the association between CMV and long-term allograft survival are discussed.