The effect of different immunoprophylaxis regimens on post-transplant cytomegalovirus (CMV) infection in CMV-seropositive liver transplant recipients

Background: The effects of different immunoprophylaxis regimens on cytomegalovirus (CMV) infection in liver transplant recipients (LTRs) have not been compared. Methods: In a cohort, we studied 343 CMV-seropositive recipient (R+) and 83 seronegative donor/recipient (D-/R-) consecutive LTRs from 2004 to 2007. Immunoprophylaxis regimens included steroid-only, steroids plus rabbit anti-thymocyte globulin (rATG), and steroids plus basiliximab. Logistic regression analysis, Cox proportional hazards regression model, and log-rank test were performed for multivariate analysis as appropriate. Results: In total, 164 (39%), 69 (16%), and 193 (45%) patients received steroid--only, basiliximab, and rATG immunoprophylaxis, respectively. CMV infection rates were 15.7% (54/343) in CMV R+ LTRs and 2.4% (2/83) in CMV R-LTRs. Among CMV R+ LTRs who received rATG, the use of at least 6 weeks of CMV prophylaxis reduced the rate of CMV infection from 24.4% (19/78) to 11.7% (9/77). In multivariate analysis, CMV R+ vs D-/R-(odds ratio [OR]=13.1, 95% confidence interval [CI]: 1.8-97.2), rATG >3 mg/kg vs steroid-only induction (OR=1.6, 95% CI: 1.1-2.3), and CMV prophylaxis 6 weeks vs >= 6 weeks (OR=2.7, 95% CI: 1.2-6.4) were independently associated with CMV infection. Subgroup analysis in CMV D-/R+ group who received rATG showed that >= 6 weeks of CMV prophylaxis significantly decreased the risk of CMV infection (OR=1.9, 95% CI: 1.1-3.9; P=.03). Conclusion: The use of rATG immunoprophylaxis increases the risk of CMV infection in CMV-seropositive LTRs, specifically in the CMV D-/R+ group. Prophylaxis with valganciclovir in this group for at least 6 weeks decreases the risk of CMV infection.