title: Analysis of renal transplant protocol biopsies in ABO-incompatible kidney transplantation.
abstract: Numerous studies have shown that protocol biopsies have predictive power. We retrospectively examined the histologic findings and C4d staining in 89 protocol biopsies from 48 ABO-incompatible (ABO-I) transplant recipients, and compared the results with those of 250 controls from 133 ABO-compatible (ABO-C) transplant recipients given equivalent maintenance immunosuppression. Others have shown that subclinical rejection (borderline and grade I) in ABO-C grafts decreased gradually after transplantation. In our study, however, subclinical rejection in the ABO-I grafts was detected in 10%, 14% and 28% at 1, 3 and 6-12 months, respectively. At 6-12 months, mild tubular atrophy was more common in the ABO-C grafts whereas the incidence of transplant glomerulopathy did not differ between the two groups (ABO-C: 7%; ABO-I: 15%; p = 0.57). In the ABO-I transplants, risk factors for transplant glomerulopathy in univariate analysis were positive panel reactivity (relative risk, 45.0; p < 0.01) and a prior history of antibody-mediated rejection (relative risk, 17.9; p = 0.01). Furthermore, C4d deposition in the peritubular capillaries was detected in 94%, with diffuse staining in 66%. This deposition, however, was not linked to antibody-mediated rejection. We conclude that, in the ABO-I kidney transplantation setting, detection of C4d alone in protocol biopsies might not have any diagnostic or therapeutic relevance.
authors.affiliation: Department of Urology, Tokyo Women's Medical University, Tokyo, Japan. setoguchi-jua@umin.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Setoguchi
authors.forename: H
authors.initials: H
authors.lastname: Ishida
authors.forename: H
authors.initials: H
authors.lastname: Shimmura
authors.forename: T
authors.initials: T
authors.lastname: Shimizu
authors.forename: H
authors.initials: H
authors.lastname: Shirakawa
authors.forename: K
authors.initials: K
authors.lastname: Omoto
authors.forename: D
authors.initials: D
authors.lastname: Toki
authors.forename: S
authors.initials: S
authors.lastname: Iida
authors.forename: S
authors.initials: S
authors.lastname: Setoguchi
authors.forename: T
authors.initials: T
authors.lastname: Tokumoto
authors.forename: S
authors.initials: S
authors.lastname: Horita
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: K
authors.initials: K
authors.lastname: Tanabe
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology*; D000328:Adult; D001706:Biopsy; D001787:Blood Group Incompatibility / Q000097:blood / Q000276:immunology / Q000473:pathology*; D015935:Complement C4b / Q000378:metabolism; D005260:Female; D006084:Graft Rejection / Q000097:blood / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007668:Kidney / Q000378:metabolism / Q000473:pathology*; D016030:Kidney Transplantation / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D000017:ABO Blood-Group System; D015935:Complement C4b