The risk of cytomegalovirus recurrence after kidney transplantation

Recurrent cytomegalovirus (CMV) infections commonly occur after kidney transplantation. We studied the impact of secondary prophylaxis and other factors on the risk of CMV recurrence. All kidney transplant recipients between 2004 and 2009 in our institution were analyzed (N = 254). Patients with CMV infection were included (N = 62). CMV infections were diagnosed with quantitative PCR. CMV D+/R- recipients received 6 months valganciclovir prophylaxis, after which DNAemia was monitored. After treatment, secondary prophylaxis with valganciclovir was given at the clinician's discretion for 2-26 weeks and CMV DNAemia was monitored. Altogether 43 reactivations and 19 primary infections occurred. Antiviral treatment with valganciclovir or ganciclovir was given to 45 patients; 34/62 (55%) patients received secondary prophylaxis for mean 62 days (range 14-180 days). CMV recurrence occurred in 14/43 (33%) seropositive patients and in 4/19 (21%) patients after primary infection. In logistic regression, delayed graft function (OR 3.4) and high viral load (> 100 000 copies/ml) at initial diagnosis (OR 5.9) predicted recurrence. Use or length of secondary prophylaxis, CMV serostatus, level of immunosuppression, HLA mismatch, antiviral treatment, or time to clearance of viremia during treatment did not predict recurrence of CMV. CMV recurrences occur commonly despite secondary prophylaxis. High viral load at diagnosis predicted the risk of recurrent CMV infection.