Československý transplantační kongres
Konferenční abstrakta 2006
Abstrakta přednášek – satelitní sympózia
INDIRECT EFFECTS OF CMV (ACUTE REJECTION, DIABETES MELLITUS, PTLD, ATHEROSCLEROSIS)
Department of Internal Medicine I, Charles University Medical School and Teaching Hospital, Pilsen, Czech Republic
Cytomegalovirus (CMV) is one of the most common pathogens causing opportunistic infections in patients after solid organ transplantation. The adverse impact of CMV infection is all the more important as it causes not only direct viral syndromes (CMV disease) but, also, indirect long-term effects. The latter include an increase in the risk for acute and chronic rejection and the onset of other opportunistic superinfections. CMV may be involved in the pathology of acute rejection by several mechanisms, including up-regulation of adhesion molecules, increased expression of MHC class II antigens on allograft tissue, and release of variety of cytokines. Direct infection of arterial smooth muscle cells and endothelial cells accelerates the development of allograft vasculopathy. CMV-encoded chemokine receptor US28 has the ability to induce smooth muscle cell migration. Moreover, CMV abrogates the vascular protective effects of endothelium-derived nitric oxide system. Some studies have demonstrated an association between CMV and subsequent development of cardiovascular complications or new-onset diabetes mellitus following renal transplantation. Hence, it comes as no surprise that CMV infection and disease have an adverse impact on the long-term patient and graft survival.
Given the medical and economic consequences, wide application of preventive measures aimed at reducing the incidence of CMV disease is clear to understand. The two main current strategies include universal prophylaxis and preemptive therapy. Considering the drawbacks of intravenous administration, the most common option includes prophylaxis with oral ganciclovir, valganciclovir, and valacyclovir with well-established efficacy in randomized trials. Also preemptive therapy approach leads to a significant reduction in the incidence of CMV disease. Prophylaxis may have some benefit in the prevention of CMV indirect effects. Nevertheless, lateonset CMV disease and ganciclovir resistance after prophylaxis are of a concern.