Korean J Transplant.  2022 Nov;36(Supple 1):S315. 10.4285/ATW2022.F-4539.

Long-term clinical outcomes of ABO incompatible kidney transplantation in patients with high baseline anti-A/B antibody titer

• Eum SH
• Lee H
• Ko EJ
• Yoon HE
• Shin SJ
• Yang CW
• Chung BH

• KMID: 2535542
• DOI: http://doi.org/10.4285/ATW2022.F-4539

Abstract

Background
ABO incompatible (ABOi) kidney transplantation (KT) has been considered to overcome donor shortage. We investigated the long-term clinical outcomes in ABOi KT in patients with high baseline anti-A/B antibody titer.
Methods
We retrospectively included 271 patients who had undergone ABOi KT from May, 2009 to February, 2021. One hundred and ninety-one patients with a baseline immunoglobulin G (IgG) titer of higher than 1:128 were assigned to the high-titer group and 80 patients with a baseline titer of lower than 1:64 were assigned to the low-titer group. We used a protocol com-posed of rituximab, plasmapheresis, and intravenous immunoglobulin (RTX/PP/IVIG). We compared the clinical outcomes of the two groups.
Results
The median follow-up periods were 59.12 months (high-titer group) and 41.53 months (low-titer group) (P=0.003). The high-titer group required more sessions of PP/IVIG than the low titer group (7.50±2.47 vs. 3.39±1.30; P<0.001, respectively). Patient survival rate at 5 years was 93.80% in high-titer and 96.30% in low-titer group. Graft survival rate at 5 years was 90.00% in high-titer and 92.60% in low-titer group. During the follow-up period, serum creatinine and urine protein-to-creatinine ratio showed no difference between two groups up to nine years (P for interaction=0.171). No significant differences were detected in the graft survival rate, patient survival rate and rejection-free survival rate between two groups. However, the infection-free survival rate was significantly lower in the high-titer group (P=0.049). The incidence of bacterial infection was higher in high-ti-ter group (45.00% vs. 28.27%, P=0.008).
Conclusions
Patients with high baseline anti-A/B IgG isoagglutinin titers had equally successful long-term outcomes as those with low titers. However, the high baseline antibody titer may require greater caution because of the higher tendency of infection.