Outcome of subclinical antibody-mediated rejection in kidney transplant recipients with preformed donor-specific antibodies

Am J Transplant. 2009 Nov;9(11):2561-70. doi: 10.1111/j.1600-6143.2009.02813.x. Epub 2009 Sep 22.

Abstract

This study describes clinical relevance of subclinical antibody-mediated rejection (SAMR) in a cohort of 54 DSA-positive kidney transplant recipients receiving a deceased donor. In 3 months screening biopsies, 31.1% of patients met the criteria of SAMR. A total of 48.9% had an incomplete form of SAMR (g+/ptc+/C4d-negative) whereas 20% had no humoral lesions. Patients with SAMR at 3 months had at 1 year: a higher C4d score, ptc score, and arteriosclerosis score, higher rate of IFTA (100% vs. 33.3%, p < 0.01) and a higher rate of transplant glomerulopathy (43% vs. 0%, p = 0.02) compared to patients without 3-month SAMR. Patients with SAMR at 3 months exhibited at 1 year a higher class II MFImax-DSA and a lower mGFR compared to patients without SAMR (39.2 +/- 13.9 vs. 61.9 +/- 19.2 mL/min/1.73 m(2) respectively, p < 0.01). The group of patients with C4d-negative SAMR at 3 months developed more ptc and IFTA lesions, and lower GFR at 1 year in comparison to biopsies without humoral lesions. SAMR is a frequent entity in KTR with preexisting DSAs and promotes subsequent GFR impairment and development of chronic AMR. C4d-negative SAMR patients displayed an intermediate course between the no-SAMR group and the C4d+ SAMR group. Screening biopsies may be useful to recognize patients more likely to develop SAMR.

MeSH terms

  • Acute Disease
  • Adult
  • Antibody Specificity*
  • Biopsy
  • Complement C4b / immunology
  • Glomerular Filtration Rate / immunology
  • Graft Rejection / immunology*
  • Graft Rejection / mortality
  • Graft Rejection / pathology
  • Graft Survival / immunology
  • HLA Antigens / genetics
  • Humans
  • Isoantibodies / immunology*
  • Kaplan-Meier Estimate
  • Kidney / immunology*
  • Kidney / pathology
  • Kidney Transplantation / immunology*
  • Kidney Transplantation / mortality
  • Middle Aged
  • Peptide Fragments / immunology
  • Proteinuria / immunology
  • Proteinuria / mortality
  • Proteinuria / pathology
  • Risk Factors
  • Tissue Donors

Substances

  • HLA Antigens
  • Isoantibodies
  • Peptide Fragments
  • Complement C4b
  • complement C4d