CMV mismatch does not affect patient and graft survival in UK renal transplant recipients

Cytomegalovirus (CMV) is one of the major infections encountered posttransplantation. UK Guidelines (2003) recommend CMV prophylaxis or screening with preemptive treatment for all high risk recipients. Studies predating the widespread use of CMV prophylaxis have shown that CMV seronegative recipients (R-) receiving a renal allograft from a CMV seropositive donor (D+) have worse outcomes than those avoiding primary CMV infection. Therefore, it has been suggested that CMV matching should be a part of the UK national deceased donor kidney allocation scheme.

We examined patient and allograft survival according to donor and recipient CMV serostatus in 10,190 UK adult and pediatric deceased donor renal transplant recipients transplanted between 2000 and 2007. We also ascertained CMV prophylaxis strategies in all UK renal transplant units.

Twenty-one of the 22 UK renal transplant centers used prophylactic oral valganciclovir for 3 months posttransplant in the D+R- transplants, having done so for a median of 4 years. Unadjusted data showed that D+R+ rather than D+R- transplants had the lowest patient and allograft survivals at 3 years posttransplant. However, after adjustment for donor age, there was no significant effect of donor and recipient CMV serostatus on allograft or patient survival.

These findings suggest that in an era where CMV prophylaxis is used routinely in D+R- transplants, the previously noted adverse effects of primary CMV infection on allograft and patient survival can be avoided (perhaps through a reduction in the incidence and/or severity of primary CMV infection), without using a CMV-matching allocation scheme.