Clinical Outcomes in Donor-Specific Antibody–Negative Flow Cytometry Crossmatch–Positive Transplant Recipients: A Systematic Review

Abstract

Background: Although it is true that donor-specific antibody (DSA) positivity is a highly validated risk factor of rejection and graft loss, it is not clear that a positive flow cytometry crossmatch (FCXM) without detectable DSA does have clinical implications. This is a valuable inter- organ transplantation and creates a dilemma in transplantation. Objective: To carry out a systematic literature review of the existing evidence on graft and patient outcomes after donor-specific antibody negative FCXM crossmatch positive transplantation. Methods: A literature search across on PubMed, MEDLINE, Embase, and Cochrane Library was performed to find out the studies assessing the outcomes in adult solid organ transplant patients with a DSA-negative and FCXM-positive result. The qualifying studies were randomised controlled trials, cohort studies, and observational studies that reported graft survival, patient survival, and outcome due to rejection. A qualitative narrative method was used to extract and synthesise the data due to the heterogeneity in study designs and immunological assessment measures. Results: Included in the review were mostly retrospective observational studies, primarily in kidney transplantation. In research, donor-specific antibody-negative FCXM-positive transplantation was correlated with associated with graft and patient survival, especially when risk-adapted immunosuppressive measures were used. Other reports showed increased early acute rejection, including antibody-mediated rejection; but the episode were usually reversible and they did not necessarily lead to poor long-term graft survival. Conclusion: The DSA-negative FCXM -positive transplantation is a transitional immunological risk phenotype and is safe to practice in the context of a carefully selected recipient. Personalized immunological evaluation and immunosuppression are required to maximize the results.