What Do Donor-Specific Antibody Changes Mean in Kidney Transplant Patients?

Abstract

Objective: The role of immunological evaluation is significant in selecting a suitable donor to reduce post-transplant complications in kidney transplantation (KTx). It is unknown how often donor-specific antibody (DSA) positivity causes rejection or how often rejection will develop in patients who do not develop DSA positivity. We aimed to evaluate the relationship between the DSA changes and the KTx patients' biochemical parameters. Methods: The study was a cross-sectional study evaluating 45 KTx patients. Demographic and clinical characteristics of the patients, pre-transplant DSA values, post-transplant DSA values, and biochemical parameters were retrospectively scanned from the hospital system. The patients' data were divided into three groups according to DSA changes. Results: DSA was negative in 21 (46%) patients and positive in 24 (54%) before transplantation. In the post-transplant follow-up, it was observed that the DSA value became positive in 7 patients and turned negative in 9 patients. Rejection developed in 22% of 9 patients whose DSA was positive before transplantation and turned negative after transplantation, and in 28% of 7 patients turned positive from negative. Estimated glomerular filtration rate (e-GFR) and creatinine levels in the post-transplant period were associated with the change in DSA. Also, e-GFR and neutrophil values were independently associated with rejection. Conclusions: Although DSA change affects kidney functions, we found that DSA positivity alone cannot predict rejection, and rejection may occur in the DSA-negative group. Neutrophil count and e-GFR changes were closely related to rejection. Therefore, DSA levels should be monitored regularly, but DSA change alone is insufficient for rejection evaluation.