Correspondence
The Economic Implications of HLA Matching in Cadaveric Renal Transplantation
N Engl J Med 2000; 342:820-821March 16, 2000
- Article
To the Editor:
In their study of the economic implications of HLA matching in cadaveric renal transplantation (Nov. 4 issue),1 Schnitzler and colleagues probably overstate the economic benefits of a strictly local organ-allocation system. They overestimate the fraction of local recipients who would receive a locally procured HLA-matched cadaveric kidney. The use of HLA-matched kidneys significantly enhances graft survival and thereby lowers post-transplantation costs. In our study,2 on which the authors based their fractions, we assumed that whereas HLA-mismatched kidneys were allocated locally, HLA-matched kidneys were shared nationally. In regions with 750 waiting patients (the local-pool size used by the authors), only 4 percent of donors would be able to provide an HLA match for a recipient,3 and not 14 percent, as the authors claim. Furthermore, only 1 to 2 percent of kidneys went to HLA-matched patients before the implementation of the United Network for Organ Sharing (UNOS) national sharing policy4; 14 percent went to HLA-matched patients thereafter. National distribution of HLA-matched cadaveric kidneys must precede local allocation for the reported economic gains in renal transplantation due to HLA matching to be achieved.
4 ReferencesSteven K. Takemoto, Ph.D.
J. Michael Cecka, Ph.D.
David W. Gjertson, Ph.D.
UCLA School of Medicine, Los Angeles, CA 900951
Schnitzler MA ,Hollenbeak CS ,Cohen DS , et al. The economic implications of HLA matching in cadaveric renal transplantation. N Engl J Med 1999;341:1440-1446
Full Text | Web of Science | Medline2
Takemoto S, Gjertson DW, Terasaki PI. HLA matching: maximizing the number of compatible transplants. In: Terasaki PI, Cecka JM, eds. Clinical transplants 1993. Los Angeles: UCLA Tissue Typing Laboratory, 1994:521-31.
3
Mickey MR ,Cook DJ ,Terasaki PI . Recipient pool sizes for prioritized HLA matching. Transplantation 1989;47:401-403
CrossRef | Web of Science | Medline4
Takiff H. The nature of shared kidneys. In: Terasaki PI, ed. Clinical transplants 1987. Los Angeles: UCLA Tissue Typing Laboratory, 1987:317-24.
Author/Editor Response
The authors reply:
To the Editor: Takemoto and colleagues point out correctly that the economic results described in our article are possible only if the current policy of sharing kidneys with zero HLA mismatches at the national level is maintained. They may not have understood that this is how the study was designed — as an economic comparison of the current system of allocating cadaveric kidneys with an alternative system in which all organs, and not just those with zero HLA mismatches, would be shared. According to the current policy, we assumed in our calculations that cadaveric kidneys with zero HLA mismatches were shared in both the local and the national allocation systems.
However, our study does not imply that national sharing of cadaveric kidneys with zero HLA mismatches is necessary to produce the best economic results in practice. UNOS policy states that for every kidney with zero HLA mismatches that is received by an organ-procurement organization, another kidney must be shared on a national level.1 It has been argued that the graft-survival outcomes of these “payback” kidneys are similar to those of kidneys transplanted locally, but the economic outcomes of these transplantations have not been studied.1 Payback kidneys generally have some HLA mismatches and have relatively long cold-ischemia times. Our study shows that longer periods of cold ischemia are associated with considerable expense. Further research will be required to determine whether the economic benefit of sharing kidneys with zero HLA mismatches is sufficient to offset the economic cost that may be associated with payback kidneys.
The current allocation system improves the clinical and economic outcomes of approximately 15 percent of cadaveric kidney transplantations through the sharing of kidneys with zero HLA mismatches, perhaps at the expense of increased cold-ischemia times for payback kidneys. We suggest in our report that discouraging transplantation of kidneys with larger numbers of HLA mismatches might be a reasonable alternative policy. Approximately half of all cadaveric transplantations involve four or more mismatches.2 Transplantations involving four or more mismatches are associated with poorer graft survival and are strikingly more expensive than better-matched transplantations. However, Takemoto et al. have shown that kidney transplantations with four or more HLA mismatches are nearly unnecessary with local allocation alone.3 Allocation programs designed to discourage transplantations involving four or more HLA mismatches could improve the clinical and economic outcomes of as many as half of cadaveric kidney transplantations without the costs in terms of longer cold ischemia that are associated with national allocation. We believe that this should be the focal message of our work.
3 ReferencesMark A. Schnitzler, Ph.D.
Robert S. Woodward, Ph.D.
Daniel C. Brennan, M.D.
Washington University School of Medicine, St. Louis, MO 63110-15931
Ellison MD ,Breen TJ ,Davies DB , et al. When perfectly HLA-matched kidneys are refused for transplant: implications for a national cooperative sharing system. J Am Coll Surg 1996;183:434-440
Web of Science | Medline2
1998 Annual report of the U.S. Scientific Registry for Transplant Recipients and the Organ Procurement and Transplantation Network: transplant data: 1988–1997. Rockville, Md.: Department of Health and Human Services, 1998.
3
Takemoto S, Gjertson DW, Terasaki PI. HLA matching: maximizing the number of compatible transplants. In: Terasaki PI, Cecka JM, eds. Clinical transplants 1993. Los Angeles: UCLA Tissue Typing Laboratory, 1994:521-31.
- Citing Articles (1)
Citing Articles
1
Nelson Goes, Anil Chandraker. (2000) Human leukocyte antigen matching in renal transplantation: an update. Current Opinion in Nephrology and Hypertension 9:6, 683-687
CrossRef
