In this issue of the American Journal of Transplantation, Dr Danovitch and his colleagues propose calculating renal transplant waiting time from the point the patient begins chronic dialysis (reference page number of this issue of AJT). The Eurotransplant experience cited in the Danovitch paper provides a sound reference for the incorporation of this proposal in the US kidney allocation system. Following the endorsement of this approach at a national conference on the waiting list in Philadelphia in March 2002, the United Network for Organ Sharing (UNOS) Kidney and Pancreas Transplantation Committee has recently approved and submitted such a proposal for public comment.
Making the system fairer to patients by computing waiting time from the onset of dialysis will address one aspect of the inequitable access to kidney transplantation. The current process of listing includes several steps (Table 1) before undergoing transplantation, each of which can be a major hurdle for a particular patient to overcome. Patients may be disadvantaged by the practices of the center at which they dialyze, where they live, their insurance coverage, comorbid illnesses, and the efficiency of the communication between the referring nephrologist and the transplant center.
|Referral of a patient from a nephrologist to a transplant center|
|Evaluation by a transplant physician and surgeon|
|Assessment of insurance coverage|
|Determination of HLA type and panel reactive antibody|
|Placement of patients awaiting accessible kidneys on a list|
Transplant centers have become aware that they should be more involved in the transition of a patient to the list. However, the focus of the transplant center upon the obstacles and inequities of patients gaining access to the list is limited because transplant centers are currently overwhelmed with the demands of care for those already listed. The waiting list has become so large that insuring that each patient on the waiting list is medically suitable for transplantation continuously has become a daunting if not impossible task. Thus, we wish to propose additional strategies to be formally considered that are in concert with the Danovitch goals:
Currently, most kidneys are transplanted into unsensitized patients (< 10%) who has been on the list for the longest waiting time. However, the clinical condition of such patients may have changed during the several years (computed by the initiation of dialysis or not) of waiting. Thus, we suggest the following:
1. The transplant center should insure that the longest waiting unsensitized patients in each blood group be recently re-evaluated; and that they are currently medically suitable for transplantation.
2. Those patients most likely to receive a 0 HLA-mismatched kidney should be identified, based upon a predictive frequency of HLA matching, and should be medically evaluated to insure ongoing suitability for transplantation.
The UNOS Kidney and Pancreas Committee is also recommending that allocation points for HLA B locus matching be eliminated from the kidney allocation algorithm and that a maximum of two points be awarded for identity at the DR locus. As patients are awarded one point for each year of waiting on the list, those who have waited at least 2 years will predictably rank higher on the allocation list for all kidneys, irrespective of their match with the donor. These changes will allow the center to focus their evaluation resources on those patients with the longer waiting times while increasing the number of kidney offers to minority candidates.
The second strategy of predicting 0-mm identity will require the input of the histocompatibility community, but such a contribution will have enormous impact upon the overwhelming task that the transplant center currently faces (1). Otherwise, it is impossible for the transplant center to keep a current account of the medical condition of all patients on the list. There must be a strategy (widely practiced) to contend with what has become an insurmountable problem, the ever enlarging list.
Although the Organ Procurement Transplant Network Final Rule requires the waiting list priority to be ordered from most to least medically urgent, the rule also recognizes that life-sustaining technologies (such as hemodialysis) may allow alternative approaches to waiting list rankings (2). Despite the observation that renal transplantation provides substantial relative improvement in patient survival, absolute survival remains excellent for patients having undergone transplantation and for wait-listed patients (3). Waiting time remains an international determinant of priority ranking of potential kidney recipients. Therefore, it is our responsibility to insure that waiting time is awarded equitably as proposed by Danovitch, and that those patients who have waited the longest and have risen to the top of the list are appropriately prepared to receive a kidney transplant.