Cytomegalovirus risk factors in renal transplantation with modern immunosuppression.

ABSTRACT

BACKGROUND: Immunosuppressive regimens have lowered the rate of kidney rejection, but with increasing immunodeficiency-related complications. New cytomegalovirus (CMV) prophylaxis also has become available. The impact of these 2 developments on CMV diseases has not been well evaluated. We conducted a randomized trial comparing a drug regimen common in the 1980s, cyclosporin A (CsA) with azathioprine (Aza), with a drug combination used most today, tacrolimus (Tac) with mycophenolate mofetil (MMF), and we analyzed CMV risk factors in kidney transplant patients. METHODS: The 300 patients included in the trial underwent the same universal prophylaxis and preemptive therapy. CMV events and risk factors were prospectively recorded. RESULTS: With preventive and preemptive strategies combined for 3 months, CMV replication was detected in 32.6% and CMV disease in 18.1% of patients. Multivariate analysis on risk factors for CMV disease were CMV donor (D)/recipient (R) matching and first month renal function (risk ratio [95% confidence interval] 1.02 [1.01; 1.04]; P=0.011), but not the immunosuppressive regimen (P=0.35). The D+/R- combination increased the risk of CMV disease by a factor of 9 (P<0.0001) when compared with D-/R- status, and a factor of 3.5 (P<0.0001) when compared with all CMV-positive recipients. Despite the 50% rate of CMV disease in the D+/R- group, no asymptomatic CMV replication was detected with the preemptive strategy. CONCLUSIONS: With modern immunosuppression, a sequential quadritherapy with Tac/MMF, and a 3-month CMV prevention strategy, the risk for CMV disease remains close to that with CsA/Aza. A CMV-negative recipient transplanted from a CMV-positive donor (D+/R-) remains a major risk factor, calling for better CMV prophylaxis or matching in negative recipients. Preemptive strategy thus appeared inefficient for this high-risk group. Transplant recipients with altered renal function should also be considered at risk.