Outcomes of 6 Human Leukocyte Antigen-Mismatched Living Donor Kidney Transplant: A Study With Biopsy Amendment.

Objectives: In this study, we examined the graft and patient survival outcomes in patients with end-stage kidney disease who received 6 HLA-mismatched incompatible living donor kidney transplant. Materials and

Methods: Patients who underwent living donor kidney transplant between January 2010 and March 2020 were evaluated retrospectively. Group A included kidney transplant recipients with 6 HLA mismatches, and group B included kidney transplant recipients with 0 to 5 HLA mismatches. Patients with <1 year of follow-up were excluded. All rejection episodes were diagnosed via Tru-Cut biopsy and histopathological evaluation.

Results: There were 15 patients in group A and 176 patients in group B. The mean follow-up was 54.1 ± 30 months. The number of patients who underwent pretransplant immune desensitization and received tacrolimus-based triple maintenance immunosuppression therapy was significantly higher in group A. In group A, there were 13 acute rejections seen in 9 patients (81<); in group B, there were 67 acute rejections seen in 51 patients (28.9<; P = .019). No differences were observed between the groups in terms of baseline glomerular filtration rate (60 ± 16 vs 61.6 ± 20 mL/min/1.72 m2; P = .76), final control glomerular filtration rate (60.7 ± 15 vs 58 ± 19 mL/ min/1.72 m2; P = .59), graft loss (0< vs 4<; P = .94), and mortality (6.6< vs 3<; P = .39).

Conclusions: The presence of 6 HLA mismatches was associated with higher rates of biopsy-proven acute rejection. However, 6 HLA-mismatched incompatible living donor kidney transplant can be safely performed in centers where posttransplant followup is supported by indication and protocol biopsies and where there is a pathological infrastructure with extensive knowledge and experience.