Controlling the Troll: Management of Cytomegalovirus Infection after Transplantation

Twenty-five years ago, Henry Balfour coined the phrase “troll of transplantation” to denote the insidious influence that cytomegalovirus (CMV) infection exerted on the outcome of transplantation (1). At that time, CMV was the most common serious pathogen in transplant recipients. Like the troll in the fairy tale, the virus was a hidden threat, latent in the recipient's or donor's tissues but ready to emerge under the pressure of immunosuppression. Although some patients only experienced subclinical CMV infection, other patients progressed to having overt CMV disease. These patients were readmitted to the hospital 1 to 2 months after transplantation and suffered weeks of fevers and debilitation. All too frequently, CMV infection led to viral pneumonia graft dysfunction or even to the patient's death. Twenty-five years ago, reduction of immunosuppression was the only treatment and rapid diagnostic tests for CMV were not available.

Now, we have drugs active against CMV infection and sensitive viral assays that can rapidly detect such infection and measure the concentration of CMV in the blood. As a result, CMV disease in transplant recipients has come under much better control. Nonetheless, the best approach to management is uncertain. Some centers with a low prevalence of CMV disease may use the “watch-and-wait” strategy of following patients and treating them if they develop clinical evidence of CMV disease. However, current opinion favors active management to prevent CMV disease during the first few months after transplantation …