Delayed onset CMV disease in solid organ transplant recipients

It is estimated that three-quarters of all patients undergoing solid organ transplantation experience new infection or reactivation of latent cytomegalovirus (CMV). The adoption of universal antiviral prophylactic strategies among high risk patients has significantly reduced the incidence of CMV infection and disease over the first three months. However, depending on the type of transplant and the pretransplant donor-recipient CMV serostatus, up to 30% of patients may develop disease after three months (late disease), or at any time later than 1-2 years following transplantation (very late disease). The occurrence of late and very late CMV, referred to here as delayed onset CMV, places patients at risk for malignancy, graft loss and mortality. Clinical management of delayed onset CMV disease may be complicated by the presentation of nonspecific or atypical symptoms. The potential for missed diagnoses may be compounded by the long term management of patients by healthcare professionals who do not practice transplantation as a primary specialty. The current clinical goal is to ensure excellent long term outcomes among transplant recipients. Therefore, the present review will discuss the natural history and risk factors, as well as the therapeutic strategies relevant to the occurrence and management of late and very late CMV disease following solid organ transplantation in adults.