ABO‐incompatible kidney transplantation can be successfully conducted by monitoring IgM isoagglutinin titers during desensitization

• Published in: Transfusion (Philadelphia, Pa.) Vol. 60; no. 3; pp. 598 - 606
• Main Authors: Kim, Hyungsuk, Choe, Wonho, Shin, Sung, Kim, Young Hoon, Han, Duck‐Jong, Park, Su‐Kil, Kwon, Seog‐Woon, Ko, Dae‐Hyun
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.03.2020; Wiley Subscription Services, Inc
• Subjects: ABO system; Antibodies; Desensitization; Graft rejection; Immunoglobulin G; Immunoglobulin M; Immunoglobulins; Immunosuppressive agents; Kidney transplantation; Kidney transplants; Survival; Transplantation
• ISSN: 0041-1132; 1537-2995
• DOI: 10.1111/trf.15672

BACKGROUND Recent advances in desensitization techniques and immunosuppressive therapy have led to improved outcomes after ABO‐incompatible (ABO‐i) kidney transplantation (KT). However, questions remain unanswered, particularly regarding which type of ABO isoagglutinin—immunoglobulin M (IgM) or immunoglobulin M (IgG)—is significantly involved in antibody‐mediated rejection (AMR). STUDY DESIGN AND METHODS We retrospectively analyzed data from 120 patients who underwent ABO‐i KT between 2012 and 2014. Preoperative plasma exchange was performed until the IgM isoagglutinin titer was 4 or less, regardless of the IgG titer. Clinical data were compared between patient groups with pre‐KT IgG isoagglutinin titer 16 or greater (high IgG; titer range, 16‐256; n = 39) and 8 or less (low IgG; titer range, −8; n = 81). RESULTS The median follow‐up periods were 59 (high IgG) and 55 (low IgG) months. Patient survival at 5 years (p = 0.314) was 100% (high IgG) and 97.4% (low IgG). Graft survival at 5 years (p = 0.480) was 100% (high IgG) and 98.7% (low IgG). AMR by anti‐ABO antibody occurred in only one patient in the low‐IgG group. CONCLUSION Patients with high pre‐KT IgG isoagglutinin titers had equally successful outcomes as those with low IgG titers. ABO‐i KT can be successfully performed by reducing the pre‐KT IgM isoagglutinin titer to 4 or less, as determined by the immediate spin tube method.