Scandiatransplant acceptable mismatch program (STAMP) a bridge to transplanting highly immunized patients

HLA. 2017 Jul;90(1):17-24. doi: 10.1111/tan.13046. Epub 2017 Apr 27.

Abstract

Background: Highly immunized patients are a challenge for organ transplantation programs. One way of increasing the likelihood of transplantation in this group of patients is to expand the possible donations by defining acceptable HLA mismatches. In the Scandiatransplant Acceptable Mismatch Program (STAMP), a de-centralized approach has been implemented in 2009.

Aims: The program has been improved during the years from utilizing HLA-A, -B, -DR matching only to include typing of all deceased donors for HLA-A, -B, -C, -DRB1 and -DQB1. The calculation of a transplantability score (TS) has been introduced in order to take both HLA and AB0 into consideration resulting in a more realistic picture of the transplantability chance.

Materials and methods: Patients were selected for eligibility and results of immunisation status were prepared in each of the 9 tissue typing laboratories, while access to the program is finally governed by a common steering group of immunologists and clinicians.

Results: In the period from March 2009 until February 2015, 96 patients were transplanted within this program. The mean recipient age was 49 years and 57% were females, 30% of the patients were first transplants and of these 93% were females. The majority of the patients had 2-5 HLA-A, -B. -DR mismatches. The allograft survival at 60 months was 79.1%. Applying the TS to the cohort confirmed that patients with a low TS score had longer waiting times.

Conclusion: The program has matured during the years and now proves to be a valid approach for transplanting highly immunized patients.

Keywords: HLA antibodies; acceptable mismatch program; highly immunized; kidney exchange program; kidney transplantation; transplantatibility score.

MeSH terms

  • ABO Blood-Group System / genetics
  • ABO Blood-Group System / immunology
  • Female
  • Gene Expression
  • Graft Rejection / prevention & control*
  • Graft Survival
  • HLA Antigens / classification*
  • HLA Antigens / genetics
  • HLA Antigens / immunology
  • Histocompatibility Testing / methods
  • Humans
  • Isoantibodies / biosynthesis
  • Kidney Transplantation*
  • Male
  • Middle Aged
  • Scandinavian and Nordic Countries
  • Tissue Donors / classification*
  • Tissue and Organ Procurement / statistics & numerical data*
  • Transplant Recipients / classification*
  • Transplantation, Homologous

Substances

  • ABO Blood-Group System
  • HLA Antigens
  • Isoantibodies