OBJECTIVE To systematically analyze the mortality risk associated with post-transplantation infection and evaluate the characteristics of subgroup populations that are more prone to mortality after infection.

METHODS A systematic search was conducted in the PubMed, Web of Science, Cochrane Library and EMBASE databases for studies published up to Sep. 2024. Data on infection-related mortality within 1 year after transplantation were collected. The pooled risk ratio (RR) and its 95% confidence interval (CI) were calculated. Subgroup analyses were performed based on demographic characteristics, immunosuppressipn regimens and types of infection.

RESULTS This study included 14 studies (n=79 130). After adjustment with the trim-and-fill method, the results showed that the mortality risk of infected recipients was 10.26 times higher than that of non-infected recipients (95% CI: 5.21-20.20, P < 0.001). Meta-regression analysis indicated that the immunosuppression induction regimen might be a source of heterogeneity in the study results. Subgroup analysis revealed that the mortality risk after infection in the group receiving antithymocyte globulin (ATG) treatment elevated compared to the non-infected group (RR=5.01, 95% CI: 2.57-9.79, P < 0.001). The mortality risk ratio between infected and non-infected patients was higher in the pulmonary and bloodstream infection groups than that in the urinary tract infection group (RRs were 6.23 and 5.56 vs. 1.45, respectively). Compared to non-infected patients after renal transplantation, the mortality risk ratio due to infection in the first year after surgery was higher than that in the fifth year (RR=3.51 vs. 1.48). No significant differences in mortality ratios between infected and non-infected patients were observed in subgroups based on age, etiology, donor source and time of infection.

CONCLUSIONS The choice of immunosuppression strategy and the type of infection may be key factors determining the mortality risk associated with post-transplantation infection. It is recommended to promptly implement pathogen-specific intervention measures and develop individualized immunosuppression regimens to reduce the risk of infection-related complications.