Risk Factors for Cytomegalovirus Infection and Its Impact on Survival after Living Donor Liver Transplantation in South Korea: A Nested Case-Control Study

Cytomegalovirus (CMV), a common pathogen, causes infectious complications and affects long-term survival after transplantation. Studies examining living donor liver transplantation (LDLT) are limited. This study analyzed the risk factors for CMV infection and its impact on the survival of LDLT patients. A nested case-control design retrospectively analyzed data from 952 patients who underwent LDLT from 2005-2021. The incidence of CMV infection for the study cohort was 15.2% at 3 months for LDLT patients managed preemptively. Patients with CMV infections were matched with those without the infection at corresponding time points (index postoperative day) in a 1:2 ratio. Graft survival was significantly lower in the CMV infection group than in the control group. CMV infection was an independent risk factor for graft survival in the matched cohort (HR 1.93, p = 0.012). Independent risk factors for CMV infection were female sex (HR 2.4, p = 0.003), pretransplant MELD (HR 1.06, p = 0.004), pretransplant in-hospital stay (HR 1.83, p = 0.030), ABO incompatibility (HR 2.10, p = 0.009), donor macrovesicular steatosis >= 10% (HR 2.01, p = 0.030), and re-operation before index POD (HR 2.51, p = 0.035). CMV infection is an independent survival risk factor, and its risk factors should be included in the surveillance and treatment of CMV infections after LDLT.