CMV Infection in CMV-Seropositive Kidney Transplant Recipients

Cytomegalovirus (CMV) infection is a major cause of morbidity in kidney transplant recipients. CMV seropositivity is common in the general population, with a reported prevalence ranging from 30 to 97% (Paya, 2001; Preiksaitis et al., 2005). After primary infection, CMV establishes life-long latency. During the past 2 decades, major advances in the management of CMV infection of transplant patients have been achieved with new diagnostic techniques and the use of antiviral agents. Most transplant centers have protocols for the diagnosis and monitoring of CMV, while strategies for the treatment of clinically significant infections as well as prophylactic and preemptive therapy have become common practice. Such strategies address both clinically significant disease and the indirect effects of CMV infection, increased risk of allograft rejection and other infections. Several guidelines been published within the last few years regarding the management of CMV in transplant patients, diagnostic procedures, and prevention by prophylaxis or preemptive therapy. The following definitions are commonly used in the transplant literature and are consistent with the American Society of Transplantation (AST) and The Transplantation Society (TTS) recommendations for use in clinical trials (Humar & Michaels, 2006; Kotton et al., 2010):  CMV infection: evidence of CMV replication regardless of symptoms  CMV disease: evidence of CMV infection with attributable symptoms. CMV disease can be further categorized as either a viral syndrome with fever and/or malaise, leucopenia, and thrombocytopenia, or as tissue-invasive disease (e.g., pneumonitis, hepatitis, retinitis, and gastrointestinal disease). A number of review articles on CMV-associated problems in kidney transplantation can aid the clinician working with these patients. These reviews include information on its clinical signs and symptoms, indirect effects, diagnosis, prevention, and treatment protocols. However, the manifestations of CMV infection vary among patients, in part depending on their CMV serostatus. In fact, the prevalence, clinical manifestations, and effects of CMV depend on the patient’s serostatus. In this overview, we summarize the current status of CMV, focusing primarily on adult kidney transplant patients who are CMV donor positive/recipient positive (CMV D+/R+).