The Effect of Cytomegalovirus Antigenemia Titer on the Efficacy of Preemptive Therapy for the Prevention of Cytomegalovirus Disease After Kidney Transplantation

There is some controversy regarding the exact cytomegalovirus (CMV) antigenemia titer that should be used as a guideline for preemptive anti-CMV therapy. We performed 634 consecutive kidney transplantations between January 2000 and June 2007. Preemptive therapy employed intravenous gancyclovir treatment when the CMV antigenemia titer was ≥50/4 × 105 leukocytes after kidney transplantation. The 634 recipients were allocated into 2 groups according to the peak CMV antegenemia: group A, CMV antigenemia titer <50/4 × 105 (n = 550); and group B, ≥50/40 × 105 (n = 84).Among the 634 recipients, 264 were positive for CMV antigenemia, and 61 developed symptomatic CMV infections. The incidence of symptomatic CMV infections in group B was significantly higher than in group A. Two cases in both groups developed tissue-proven CMV disease: group A CMV colitis and CMV nephritis, and group B, 2 cases of CMV colitis. Graft and patient survival rates in groups A and B at 5 years posttransplantation were not different.The authors concluded that a CMV antigenemia titer of ≥50/4 × 105 leukocytes can be considered an appropriate guideline for preemptive anti-CMV therapy.