Donor Graft Cytomegalovirus Serostatus and the Risk of Arterial and Venous Thrombotic Events in Seronegative Recipients After Non-Thoracic Solid Organ Transplantation

Background: Cytomegalovirus (CMV) is the most common opportunistic pathogen, following solid organ transplantation (SOT), that leads to direct and indirect effects. The aim of this study was to assess the impact of CMV exposure at transplantation on the rate of posttransplant thrombotic events (TEs).

Methods: We conducted a retrospective cohort study of patients transplanted at the University of Alberta Hospital between July 2005 and January 2018. We included adult SOT CMV-seronegative recipients at transplantation who received an allograft from either a seropositive donor (D+/R-) or a seronegative donor (D-/R-).

Results: A total of 392 SOT recipients were included: 151 (39%) liver, 188 (48%) kidney, 45 (11%) pancreas, and 8 (2%) other transplants. The mean age was 47 years, 297 (76%) were males, and 181 (46%) had a CMV D+/R- donor. Patients in the CMV D+/R- cohort were slightly older (51 years versus 48 years in the D-/R- cohort; P = .036), while other variables, including cardiovascular risk factors and pretransplant TEs, were not different between groups. Overall, TEs occurred in 35 (19%) patients in the CMV D+/R- group, versus 21 (10%) in the CMV D-/R- group, at 5 years of follow-up (P = .008); the incidence rates per 100 transplant months were 5.12 and 1.02 in the CMV D+/R- and CMV D-/R- groups, respectively (P = .003). After adjusting for potential confounders with a Cox regression model, a CMV D+/R- transplantation was independently associated with an increased risk of a TE over 5 years (adjusted hazard ratio, 3.027; 95% confidence interval, 1.669-5.488).

Conclusions: A CMV D+/R- transplantation is associated with an increased risk of a TE posttransplantation.