Cytomegalovirus infection has been associated with increased morbidity and mortality after transplantation and with diminished graft survival. After transplantation, more than 75% of solid organ transplant patients are newly infected with cytomegalovirus, or latent cytomegalovirus infection may be reactivated. The objective of our study was to evaluate reactivation rate of cytomegalovirus infection after kidney transplantation in Kaunas University of Medicine Hospital and its relation to anticytomegalovirus prophylaxis. A retrospective review of all kidney transplants performed between May 2000 and December 2006 was conducted. We analyzed the prevalence of cytomegalovirus in the groups of donors and recipients, and risk categories were defined for cytomegalovirus infection/disease in transplant patients. During this period, a total of 93 transplantations were performed in 56 men (60.2%) and 37 women (39.8%). The mean age of recipients was 41.04+/-12.74 years. There were 33 (68.7%) men and 15 (31.3%) women in the group of donors; their mean age was 39.49+/-14.81 years. Patients at high risk for the development of cytomegalovirus infection/disease were defined as those who had donor-positive/recipient-negative serostatus (D+/R-), and they made up 5.4% of all patients. Intermediate-risk patients with cytomegalovirus infection (D+/R+ and D-/R+) accounted for 73.1% and 15.1% of all recipients, respectively; 6.4% of patients were at low risk (D-/R-). Anti-cytomegalovirus prophylaxis with i/v ganciclovir was given during the period of hospitalization in all cases, except when there was a D-/R- combination, or when the transplant was removed in the early period after transplantation. The reactivation of cytomegalovirus infection was observed in 23 patients (24.7%). We have observed 41 episodes of cytomegalovirus infection, but during this period, no patient developed cytomegalovirus disease that might cause lethal outcome.