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Establish Minimum Kidney Donor Criteria to Require Biopsy

eye iconAt a glance

Current policy

Procurement kidney biopsies are a tool that OPOs and transplant doctors use to assess a deceased organ donor’s kidney for organ damage and potential kidney function. Over the years, kidney biopsies have become more widely used, but their usage varies greatly across the country. Currently, OPTN policy does not set a minimum standard for when a kidney biopsy must be performed.

Supporting media


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Proposed changes

  • OPOs will be required to perform a kidney biopsy on deceased organ donors who meet any of the following, excluding donors less than 18 years old:
    • Urine output of less than 100ml in 24 hours
    • Donor has received hemodialysis or other renal replacement therapy either during most recent hospital admission or in the course of donor management
    • History of diabetes, including a hemoglobin A1c of 6.5 or greater during donor evaluation and management
    • KDPI greater than 85%
    • Donor age 60 years old or greater
    • Donor age 50-59, and meets at least two of the following criteria:
      • History of hypertension
      • Manner of death: Cerebrovascular Accident
      • Terminal creatinine of 1.5 mg/dL or greater

Anticipated impact

  • What it's expected to do
    • Standardize kidney biopsy usage
    • Streamline communication between OPOs and transplant hospitals
    • Improve kidney allocation efficiency
  • What it won't do
    • It will not limit when an OPO can perform a kidney biopsy including when a deceased organ donor does not meet the minimum criteria.

Terms to know

  • Biopsy: a tissue sample from the body, removed and examined under a microscope to diagnose for disease, determine organ rejection, or assess donated organs or tissues.
  • KDPI: Kidney Donor Profile Index, a mathematical system used to classify deceased donors to help improve kidney allocation efficiency.
  • Hemoglobin A1c: a test used by medical professionals to assess pancreas function. A high hemoglobin A1c may be an indicator of diabetes in a patient.

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eye iconComments

UC San Diego Health Center for Transplantation | 03/23/2022

CASD does not support this proposal to establish minimum kidney donor criteria to require biopsy. The goal of policy should be to decrease the number of unnecessary biopsies, thus increasing kidney utilization. Codifying these incredibly broad criteria into policy is likely to have the opposite effect as literature and experience suggest that few providers utilize pre-procurement biopsy alone to determine suitability for transplantation as there is a weak correlation between procurement biopsy findings and clinical outcomes in recipients, including graft failure; but many providers do decline otherwise acceptable (although perhaps older or higher KDPI) kidneys based on biopsy findings alone. The challenges of obtaining samples, and more importantly, having them read by an expert in the context of transplant suitability, renders the tests moderately informative at best. Absent a standardized approach to the biopsy process (who recovers the sample, how it is processed, read and reported) we echo Mayo Clinic’s recommendation to facilitate ongoing dialogue between OPOs and transplant programs to employ expeditious transplant center pathology re-review in marginal cases to increase transplantation of all donor kidneys.

OPOs of LifeLink of Florida, LifeLink of Georgia, and LifeLink of Puerto Rico | 03/23/2022

Thank you for the opportunity to provide public comment for the policy proposal to “Establish Minimum Kidney Donor Criteria to Require Biopsy.” The Organ Procurement Organizations (OPOs) LifeLink of Florida (FLWC), LifeLink of Georgia (GALL), and LifeLink of Puerto Rico (PRLL) oppose implementation of this proposed policy that mandates renal biopsy at time of procurement as we believe the additional requirements for kidney biopsies will adversely impact kidney utilization. Research findings, as noted below, indicate renal biopsy does not significantly improve long term graft success/failure. Journal of American Society of Nephrology (JASN) published a study (JASN 2019 by Loupe et al.) which looked at 1,103 kidneys that were discarded in the United States (US) because of histologic findings and matched them to similar kidneys transplanted in France. The study revealed an expected allograft survival of 93.1% at one year, 80.7% at 5 years and 68.9% at 10 years of the kidneys discarded in the US. A 2019 Journal of the American Medical Association (JAMA) paper, also from France, found a US discard rate of 17.9 % 2004-2014 (27,987/156,089) versus France’s rate of 9.1% (p value less than 0.001) 2732/29,984). They then applied the French criteria to the “non-used” US kidneys and stated 62% of the discarded kidneys from the US would have been transplanted in France. The American Journal of Transplantation (AJT) published an article in 2019 which states after 20 years of demonstrating that kidney biopsies performed at the time of recovery provide very limited insight regarding the eventual outcome of renal allografts, over 50% of kidneys are still biopsied. The article also noted after adjustment for donor factors, biopsy was associated with more than 3 times the likelihood of non-use (3.51). Within our Donation Service Areas, pathology services are not always readily available in all donor hospitals which would require specimens be transported thereby increasing cost, decreasing kidney placement efficiency, and prolonging cold ischemic time prior to organ transplantation. The policy does not address how transplant centers will use biopsy results. If the biopsy result is within their criteria for acceptance, will there be an accountability for kidney offers meeting their filters that are subsequently declined? Additionally, when biopsies are performed by the OPO, will there be additional accountability and/or criteria regarding re-biopsies performed by the accepting transplant center? Most interpretations of renal biopsies are done by pathologists who have little to no expertise in renal histology, therefore the accuracy rate of interpretation is unconfirmed except for estimating the percentage of glomerulosclerosis as compared to an expert panel. Additionally, frozen section specimens, which is all we depend upon in the field (real time), have only a moderate to poor correlation with paraffin embedded slides which take an additional 12 to 24 hours to prepare. While we appreciate the desire to standardize practice, we believe this policy will increase the number of kidney biopsies we perform without increasing the number of kidneys transplanted. Unfortunately, the proposal does not address inconsistent transplant center practice behavior in how biopsy results are considered. The science behind a procurement biopsy needs to be studied and better understood to increase quality and reliability and ultimately tied to graft survival to inform future policy development that increases kidney utilization. Mandating biopsies, if the past can predict the future, will only continue to increase our non-use on medically complex kidney offers.

HonorBridge | 03/23/2022

While HonorBridge acknowledges the need for standardization of criteria for kidneys that are appropriately biopsied, we are concerned that the overall impact of this policy will be an increase in discard rates of kidneys that can be safely transplanted. HonorBridge shares the concern that there is lack of data demonstrating that biopsies impact outcomes. We encourage the committee to develop policies that decrease the number of biopsies performed and increase organ utilization.

Anonymous | 03/23/2022

The OPO Committee thanks the Kidney Transplantation Committee for their efforts in developing this proposal. The OPO Committee has concerns about requiring the performance of procurement kidney biopsies. Several members felt that biopsies are over-performed, and over-relied upon in organ evaluation. One member commented that policy should focus on decreasing biopsy rates, and recommended including language to limit the performance of procurement kidney biopsies. Several members expressed concerns regarding accepting transplant programs performing their own biopsies and declining kidneys at high cold ischemia times due to their own biopsy results. One member recommended including language to prevent or strongly discourage accepting programs from performing their own procurement kidney biopsies, particularly if an OPO has not biopsied that kidney. Members expressed support for more minimal criteria. One member recommended removing the ECD definition from the criteria, noting that KDPI greater than 85 percent encapsulates most ECD definition donors. Members acknowledged that kidneys meeting this criteria will typically always be biopsied. A member recommended the Kidney Committee refer to the AOPO and ASTS recommendations for kidney biopsy criteria in considering simplifying the proposed criteria. One member suggested including another criterion indicating AKI, such as highly elevated creatinine. Several members agreed that a biopsy should only be required if the accepting or primary transplant program’s surgeon requests it. Some members remarked that both of the biopsy proposals do not address issues related to wedge biopsy, pathologist experience and reproducibility, or reliability of biopsy results in predicting graft function. Another member commented that inattention to quality and accuracy and lack of standardization in how biopsies are collected, prepared, read, and reported also impact allocation efficiency, and should be addressed in efforts to standardize and improve biopsy practices.

Anonymous | 03/23/2022

5 strongly support, 5 support, 1 neutral/abstain, 1 oppose, 0 strongly oppose

Humana | 03/23/2022

Humana supports the proposal to standardize the reporting requirements for kidney biopsies.

American Society of Transplantation | 03/22/2022

The American Society of Transplantation does not support establishing criteria for biopsy requirements at this time. While the proposal is laudatory for the sake of national consistency, the current criteria are too broad. The Society believes that data are currently lacking to demonstrate the biopsies impact outcome. As written, the proposal will likely increase rather than decrease the number of biopsies obtained and therefore increase the number of discards due to abnormal biopsy findings. The Society’s Communities of Practice (COPs) members suggest that minimum biopsy criteria should be narrowed to kidneys from donors with KDPI>85%, diabetes, and/or anuria. COP members also suggest adding proteinuria >1g. Without this addition, there are concerns “any diabetes” could lead to numerous biopsies that wouldn’t normally be requested now (e.g., well-controlled diabetes for less than 5 years in a young donor with no protein in urine and good UO). A mandate that biopsies must be performed in a set of circumstances risks an increase in the use of procurement biopsies, which may add to cold ischemia time and potentially reduce organ utilization. The proposal does not address the variability of reporting of procurement biopsies. Many donor hospitals do not have sufficient infrastructure to accommodate the proposed changes including a dedicated or available renal pathologist. Variable and potentially unreliable results could lead to increased discards of otherwise usable kidneys. The OPTN should consider a system of standardized central reporting of biopsies by a pathologist who specializes in reading procurement biopsies. While we recognize the need for uniform biopsy criteria, AST cannot support this proposal until criteria are established that reduce the number of biopsies performed and do not decrease organ utilization.

View attachment from American Society of Transplantation

Association of Organ Procurement Organizations | 03/22/2022

Association of Organ Procurement Organizations strongly oppose Establish Minimum Kidney Donor Criteria to Require Biopsy proposal.

View attachment from Association of Organ Procurement Organizations

Mayo Clinic Arizona, Florida, and Minnesota Kidney Transplant Medical and Surgical Directors | 03/22/2022

Aggressive acceptance of deceased donor kidney offers can translate into increased access to transplantation for all patients. Our centers and others have demonstrated variable reliability of kidney procurement biopsy performed and interpreted at the donor hospital. This includes inadequate sample quality, frozen section artifact, and inexperienced pathologic interpretation leading to increased organ discard. We have simultaneously demonstrated the role of transplant center biopsy interpreted by an experienced renal pathologist to successfully increase utilization of marginal kidney allografts. We encourage OPOs work towards digitalization of all preimplant kidney biopsy slides to be interpreted by expert renal pathologists to provide high quality initial interpretation. We encourage careful use of adequate donor kidney biopsies; however, we are concerned the current criteria are stringent and may lead to an unintended increase in organ discard. We suggest ongoing dialogue between OPOs and transplant programs to employ expeditious transplant center pathology re-review in marginal cases to increase transplantation of all donor kidneys. We caution utilizing pre-procurement biopsy alone to determine suitability for transplantation. Furthermore, the current criteria do not include a biopsy provision for young donors with severe acute kidney injury not yet requiring hemodialysis or demonstrating urine output

National Kidney Foundation | 03/22/2022

The National Kidney Foundation appreciates the opportunity to comment on the OPTN proposal, "Establish Minimum Kidney Donor Criteria to Require Biopsy."

View attachment from National Kidney Foundation

Richard Rothweiler | 03/22/2022

I appreciate the opportunity to provide public comment. I do not support the proposal to establish minimum kidney donor criteria to require a kidney biopsy because the proposal does not lead to an increase in kidney transplants, a decrease in kidney discards, or a reduction in unnecessary kidney biopsies. To align more closely with OPTN's strategic objectives, we believe that increasing kidney utilization should be the primary objective of policy development in this area. According to table 1 in the proposal, more than 90% of 2019 deceased donor kidneys that met the proposed criteria were biopsied, suggesting that obtaining a kidney biopsy is not a problem to be solved. This policy will mandate biopsies on the remaining 10% without any real benefit, but rather a decrease in kidney utilization. If a surgeon accepts a kidney without biopsy, which meets the proposed criteria, we would be obligated to unnecessarily biopsy the kidney, thus increasing the risk of discard despite having organ acceptance without a biopsy. This approach is counterintuitive and should be discouraged. We should set this standard based on the most aggressive transplant center acceptance practices, rather than the least. The goal of policy development in this area should be to decrease the number of unnecessary biopsies, thus increasing kidney utilization. Between 2014-2018, there were 3,467 biopsies performed on donors with a KDPI

Mid-America Transplant | 03/22/2022

Please see attached document.

View attachment from Mid-America Transplant

Anonymous | 03/22/2022

10 strongly support, 11 support, 1 neutral/abstain, 0 oppose, 1 strongly oppose - Members of the region support the proposal. One member noted that establishing minimum standard criteria for biopsy is a step in the right direction; however, with these current parameters, there may be more kidneys being biopsied. Another member noted that the OPTN should develop a national strategy to have standard pathology review by renal pathologists to avoid the inaccurate reports that are common. In addition, all OPOs should use an electronic review program so transplant centers can access the virtual slides and review the pathology. It was also stated that it might be helpful to include data on which specific elements of the biopsy influence post-transplant graft survival. Summaries of the relevant data might be helpful to the community. Another member suggested that for all KDPI < 85 donors, biopsies have the potential to increase discards, so indications for mandatory biopsies should be as limited as possible. The United States’ over reliance on biopsies, compared with Europe, is counterproductive. Another member applauds the OPTN’s effort to standardize kidney biopsies which will lend some standardization going forward to utility and impact of biopsies. Eventually, once the utility of standardized biopsies are realized, the findings could be incorporated into making KDPI more granular. However, the member noted their frustration with the unreliability of frozen section biopsies. There should be standardization of requiring permanent sections performed in pathology labs with renal pathologists. Lastly, another member noted that this policy proposal needs to address the over reliance on biopsy results which can be detrimental to organ utilization. Also, the requirement for biopsies for donors with KDPI > 85 as well as the old expanded criteria donor qualifications seems redundant.

Anonymous | 03/21/2022

Sentiment: 6 strongly support, 5 support, 1 neutral/abstain, 0 oppose, 1 strongly oppose. Comments: Overall the region supported the proposal. Several attendees commented that standardization in who is reading biopsies is more important than standardization in criteria. These attendees encouraged the Committee to consider pursuing requiring transplant professionals to read biopsies. A member recommended that the Committee also focus on initiatives that drive increased utilization in light of evidence showing that kidneys in the US are declined due to biopsy results, while kidneys with similar attributes are used with good outcomes elsewhere. One attendee expressed concern that these criteria are too strict and will lead to increased discards. The attendee recommended the following criteria instead – 1) Eliminate a set age, 2) adjust CVA to exclude ruptured aneurysm, 3) exclude well controlled diabetes and well controlled HTN less than 10 years, provided the terminal creatinine is less than 2.0.

Anonymous | 03/21/2022

Sentiment: 6 strongly support, 8 support, 2 neutral/abstain, 0 oppose, 0 strongly oppose. Comments: Overall, members of the region supported the proposal. There were concerns that the requirements are too broad and many result in unnecessary biopsies. Several commenters voiced concerns about including the former expanded criteria donor criteria as part of the criteria to require biopsy due to the heavy overlap with donors that have a KDPI greater than 85%. It would make things overly complicated for OPOs and could greatly increase the number of required biopsies. There were suggestions to remove the expanded criteria donor criteria and require biopsies from donors with a KPDI greater than 75%. Another member noted that the proposal may not lead to increased access to kidneys. By requiring biopsies, it may make programs less likely to accept kidneys that they would have otherwise accepted. It was suggested that the proposal should instead focus on educate them on best practices for when to perform a biopsy.

Anonymous | 03/18/2022

Sentiment: 6 Strongly Support; 6 Support; 0 Neutral/Abstain; 0 Oppose; 0 Strongly Oppose. Comments: Overall, the region supported the proposal. One member asked that biopsies also be shared digitally, which was supported by another member. Another member requested a more liberal set of conditions where biopsy could be available upon request. The member also shared that while standardizing requirements is a good idea, the decision to biopsy is not a binary one, so there will be instances that call for exceptions to the criteria as laid out in the proposal. One individual commented their institution supports the criteria overall, but brought up concern with the situation of when an OPO performs a biopsy and then the program does their own biopsy, receives conflicting results, and then declines the kidney based on the second biopsy. Another attendee stated support for an overall limit on the number of biopsies done. A member commented that there are too many biopsies done now in the region and expressed concern that these criteria would do nothing to impact that. An attendee asked that the committee consider how to handle if a donor hospital does not have the resources to allow for a biopsy, so that the OPO can continue to recover and allocate the kidney without a biopsy, without it being a noncompliance event. The attendee added that OPOs need to maintain certain flexibility in performing biopsy of kidneys outside of the proposed criteria.

Live On Nebraska | 03/18/2022

Requiring an OPO to biopsy a kidney may have negative affects which could lead to more kidney discards. The biopsy interpretation can vary widely based on renal pathology training or lack thereof. The parameters proposed are confusing and unclear. For example, a kidney will be required to be biopsied if the donor has a urine output of less than 100ml in 24 hours. When does the 24 hours apply? Is this the last 24 hours prior to cross-clamp? Any 24 hour period during the final hospital admission? Or another timeframe not listed here? Secondly, within this proposal, OPOs will be required to biopsy kidneys on donors age 50-59, and meet at least two of the following: history of hypertension, manner of death: CVA, terminal creatinine of 1.5 mg/dL or greater. What does history of hypertension mean? Is this within the last year? 5 years? 10 years? This type of criteria, if established, must be well-defined in order for an OPO to be compliant to this type of policy. All in all, we firmly believe that procurement biopsies do not correlate with transplant outcomes or increased utilization. Therefore, biopsy practices should be agreed upon by the OPO and accepting transplant center and not mandated by the OPTN. We strongly encourage reconsideration of this policy by the committee and urge them to consider policies that promote increased kidney utilization.

Amanda Bailey | 03/18/2022

I agree with this criteria. I would consider adding DCD as a criteria. This is a necessary change needed to bring uniformity and improve organ allocation in a timely manner.

Anonymous | 03/17/2022

Sentiment: 2 strongly support, 7 support, 0 neutral/abstain, 1 oppose, 1 strongly oppose. Comments: One member commented that the criteria should not include anuria, or urine output of less than 100ml in 24 hours. Another member commented that HgA1c affects kidney function and should be required. There was also a recommendation from a member that the OPTN consider policy to standardize kidney pumping.

American Society of Transplant Surgeons | 03/17/2022

American Society of Transplant Surgeons supports.

View attachment from American Society of Transplant Surgeons

Anonymous | 03/16/2022

The Transplant Coordinators Committee thanks the OPTN Kidney Transplantation Committee for their proposal Establish Minimum Kidney Donor Criteria to Require Biopsy and the opportunity to provide feedback. The Committee supports their efforts to improve biopsy standardization and provided comments for consideration. It was felt that there could be an unintended increase in cold ischemic time due to mandated biopsies for programs that use external pathology staff. Additionally, the Committee expresses concern that there could be an increase in costs for Organ Procurement Organizations surrounding the procurement and shipping of biopsy slides to external pathology laboratories. It was suggested that, in areas that do not have pathology access, biopsy slides or images thereof could be required to be sent to accepting programs in place of the required biopsy being performed. Furthermore, the Committee feels that, in instances where kidneys meet the procurement biopsy requirements but already have an accepting program, the transportation process should not be delayed to gather information from a required biopsy. Finally, surrounding the thresholds specified for anuria and renal replacement therapy, a member felt that in certain rush trauma cases, these would not be sufficient.

Gift of Life Donor Program | 03/14/2022

Thank you for the opportunity to provide public comment for the policy proposal “Establish Minimum Kidney Donor Criteria to Require Biopsy.” Gift of Life Donor Program opposes implementation of this proposed policy and believes that the kidney committee should develop policies surrounding the necessity of biopsies that promote increased kidney utilization. There is currently an overreliance on kidney biopsy results in the United States to determine utilization. Research shows decision makers routinely decline a kidney based solely on the results of the procurement biopsy. A French study by Peter Reese and team found that “About 45% of 1103 United States kidneys discarded because of histologic findings could be accurately matched to very similar kidneys that had been transplanted in France; these discarded kidneys would be expected to have allograft survival of 93/1% at 1 year, 80.7% at 5 years, and 68.9% at 10 years.” The study went on to conclude that, “Many kidneys discarded on the basis of biopsy findings would likely benefit United States patients who are wait listed” (doi: 10.1681/ASN.2020040464). Most of the deceased donor kidneys in Europe are not biopsied and have better utilization. While we appreciate the desire to standardize practice and reduce the number of kidney biopsies performed, we do not believe this policy will have the intended effect. The proposal only addresses minimum criteria and does not address OPO variation in performing biopsies or address inconsistent transplant center practices in how those results are considered. The challenges associated with a fresh frozen, wedge biopsy is well established in the literature. This policy proposal fails to address the well-known consistency and reliability issues of collection and interpretation of kidney biopsies. There is often conflict in biopsy interpretation between fresh frozen and permanent sections, known quality issues with wedge biopsy collection, variation in experience and training of pathologists who read the fresh frozen sections, and frequent disagreement in interpretation regardless of expertise. The science behind a procurement biopsy needs to be studied and better understood to increase quality and reliability and tied to graft survival to inform future policy development that increases kidney utilization. There is also significant variation in transplant center practice in interpreting what a biopsy results means for an individual patient. The policy will not reduce variation in 1) what donor kidneys get biopsied, 2) how those biopsies are performed and interpreted by pathologists or 3) how transplant centers use the results. Without addressing these issues the policy will not make kidney allocation more efficient nor will it increase the number of kidneys transplanted. Additionally, if such a policy is implemented then it should also include policy surrounding transplant center use of a filter for biopsy results and operational considerations for transplant center accountability, particularly if a biopsy is not required and the center performs their own after acceptance, leading to a turn down. We strongly encourage reconsideration of this policy by the committee and urge them to consider policies that promote kidney utilization .

Anonymous | 03/11/2022

The Operations and Safety Committee thanks the OPTN Kidney Transplantation Committee for their efforts on the Establish Minimum Kidney Donor Criteria to Require Biopsy proposal. The Committee supports the proposed set of criteria. The Committee suggests that renal replacement therapy and fluid management should be distinguished. For example, “renal replacement therapy (excluding fluid management). The Committee also suggests that the proposal should consider establishing guardrails for when a second biopsy is acceptable to reduce the occurrence of two biopsies being performed with varying result interpretations. The Committee encourages that the community should progress towards whole slide scanning/digitalization and a centralized pathology service for reading results. The Committee emphasizes that transplant programs need as much information as available.

American Nephrology Nurses Association (ANNA) | 03/11/2022

ANNA supports.

View attachment from American Nephrology Nurses Association (ANNA)

Anonymous | 03/08/2022

I think this could improve utilization of kidneys. I do feel emphasis on not excluding biopsy under other conditions is important. Standardization in reporting is much needed as well. I see variations across some OPO's currently.

Anonymous | 03/02/2022

• Sentiment: 5 strongly support, 9 support, 2 neutral/abstain, 1 oppose, 1 strongly oppose • Comments: Attendees provided the following comments and recommendations: o There is as much inconsistency in biopsy as there are in acceptance practices. o Standardized acceptance criteria will help standardize acceptance and affect variables such as who is taking call. o The proposal may increase costs by requiring too many biopsies on organs that may eventually be rejected. o Policy should provide guidance on what to do if pathology is not available at a community hospital. Standardizing the form is a good idea, but conditions such as nodular mesangial glomerulosclerosis may be difficult for a community-based pathologist to discern. The donor selection criteria for biopsy may be too wide. o The only criteria should be KDPI over 85. The commenter noted this is their program’s policy, and their kidney discards have decreased and kidney transplants have increased. European data supports this practice. o The committee should consider adding a history of diabetes greater or equal to 5 years, and urine protein greater or equal to 300mg/dl to the Criteria to Require Biopsy.

Anonymous | 02/24/2022

It makes perfect sense .

Anonymous | 02/23/2022

4 strongly support, 7 support, 3 neutral/abstain, 4 oppose, 0 strongly oppose - Region 8 generally supported this proposal with some opposition. A member asked if there will be an increase in discards since there is variation in how a biopsy is interpreted. Several members pointed out that this proposal could lead to an increase in discards because there is variability in how members interpret biopsies. A member commented that this proposal is a good starting point, and that members are performing too many donor kidney biopsies but unfortunately, discarding too many kidneys that could be transplanted. A member asked if procurement biopsies correlate with transplant outcomes. The member thought these parameters were confusing and excessive, and believes that biopsy requests will significantly delay allocation and increase organ cold time. A member followed-up that procurement biopsies do not correlate with transplant outcomes. A member asked if there are reasons, other than lack of standardization of biopsy criteria, as to why current biopsy rates vary across OPOs. The member also asked why the age of 60 is a stand-alone criteria. A member suggested tracking which OPOs and transplant centers do not use these parameters for requesting biopsies. A member noted that policy shouldn’t require kidneys to be biopsied if the OPO and transplant center do not want a biopsy. An institution supported this proposal and commented that the proposal must explicitly state that these are the minimum criteria for which donors must get a biopsy but not the only criteria for a donor to get a biopsy. It expressed concern that OPOs might use this policy as the only required criteria for donors to get a biopsy. It suggested that there should be an option for the surgeon to exercise discretion. Several members supported standardization of information obtained in a biopsy and minimum standards to perform biopsies. A member commented that it is important to create a platform, similar to radiology, where the center is able to view the biopsy slides, in real time, during the allocation and acceptance stage.

Anonymous | 02/18/2022

1 strongly support, 18 support, 2 neutral/abstain, 2 oppose, 3 strongly oppose - Region 4 generally supported the proposal. Some commenters expressed concern about biopsies being used to rule out kidneys rather than to increase utilization. They went on to comment that doing more biopsies would result in increased discards. Another attendee commented that any policy to standardize biopsy criteria should result in fewer biopsies. There was also concern from several commenters that different labs have different results with wide variation and inconsistencies and should not be used to rule out a kidney. They went on to recommend the committee look at reasons for discards when they are related to biopsies. One attendee commented that the OPTN should not tell clinicians when they need a biopsy. They went on to comment that the clinician should determine what information they need to ensure the right organs get into the right patient. They added that the primary issue is the quality of the biopsy and the standardization of pathologists. Another attendee commented that they supported gathering data and the effort to try to standardize, but are doubtful that data will result in any meaningful reduction of biopsy use. They added that much of the procedure is based in legacy and not evidence.

Christopher Anderson | 02/17/2022

Standardized biopsy criteria seems reasonable, but the proposed criteria are too stringent and increase the OPO resource demands. Based on practices at our local OPO, we have actually decreased the discard rate by not biopsying kidneys with a KDPI < 85%. Biopsy results are often used as a "reason" for turn down. I think it is important to allow OPO's to biopsy kidney's that they know are usable at their discretion. Increasing resource usage via mandatory biopsy will slow allocation and result in more discards due to CIT. Being less restrictive with biopsy criteria is more in keeping with the CMS initiatives to increase kidney utilization and decrease discards.

Anonymous | 02/16/2022

6 Strongly Support, 17 Support, 4 Neutral/Abstain, 4 Oppose, 2 Strongly Oppose - A member pointed out that assuming the OPO doesn’t grant biopsy waivers, a potential consequence could be that the OPO refuses to do a biopsy because it doesn't meet criteria, a center accepts the kidney, does their own biopsy and then refuses the kidney on the basis of their own biopsy. Several members support proposal’s intent and standardization of criteria and OPO practices. Several members suggested to add a requirement for the digital pathology slide. A member pointed out that a biopsy seems like it would be quick but noted that a biopsy can increase hours to allocation and the committee needs to make sure that the policy doesn’t extend preservation times. A member asked if an OPO isn't able to obtain all the information since that OPO is located in a small community hospital, how will that impact compliance? A member requested the committee consider clarifying that transplant programs should retain the right to request biopsies on donors outside the proposed criteria to avoid OPOs declining. A member supported the proposal overall but felt there needs to be additional work to understand how this will be operationalized to ensure policy compliance and that the policy furthers utilization. A member commented that one of the best predictors of kidney discards or kidney non-utilization is the presence of a kidney bx. The criteria under which that a procurement biopsy must be performed seems vague and proscriptive. The member agrees that the OPO should be required to perform a biopsy with the required criteria if a transplant program requests a biopsy. However, if the accepting center and the backup center do not request biopsy, and the OPO still performs the biopsy, then there could be an increase in discards. The member agrees with routine and mandatory biopsy of a more selective set of kidneys when it is requested by transplant centers. A member noted that his institution supports this proposal but wants the criteria to expand to: 1) urine output of 1.5, and 3) biopsy Covid + donors since they have seen some kidneys with necrosis/infarcts.

Anonymous | 02/16/2022

6 Strongly Support, 7 Support, 1 Neutral/Abstain, 1 Oppose, 0 Strongly Oppose - Overall, members of the region support the proposal. A member noted that not every kidney needs to have a biopsy and establishing a criteria for biopsies will solve this issue. Another member voiced their support of the proposal, but it will be important for the OPTN to allow OPOs and transplant centers to request and perform biopsies aside from these minimal criteria. For example, if the WIT for DCD kidneys exceeds 60 minutes, it would be important to know amount of thrombosis is present, especially when the kidneys are discolored after in situ flush. It was also noted that, although there are concerns that biopsies may increase discard rates, biopsies could positively impact outcomes. Unexpected information on a biopsy could potentially reduce the risk of graft loss. Another member raised concern about how the policy will be operationalized given that one missing piece of the proposal is the lack of standardized pathologic assessment. There were concerns raised over the proposed criteria for diabetes history. One member noted that instead of any history of diabetes, the committee should consider a more focused criteria like a history of diabetes greater than five years or a certain HgBA1C level. Another member stated their opposition to the diabetes criteria, adding some European nations are seeing increases in kidney transplants without performing a biopsy. There is no data that suggests doing more biopsies or standardizing biopsies will lead to more kidneys being transplanted. Another member stated that it appears OPOs are moving away from biopsies as the standard and this proposal may conflict with that strategy. Lastly, an OPO member noted that more evaluation on biopsy practices is needed for this proposal and offered several suggestions. There needs to be a crosswalk between the new criteria and what already falls into the KDPI factors that would put donors above 85% and require a biopsy. Biopsies needs to be read by someone who is skilled in reading transplant biopsies, and data needs to be shared about how many kidneys were declined because of lack of biopsy and how many were declined because of incongruent information from the biopsy as compared to the clinical picture. Additionally, is there data that demonstrates that kidneys would have been used if a kidney biopsy was available? The member supports additional data that helps improve transplanting more kidneys, but is not convinced that the proposal will accomplish that goal.

Thomas Molony | 02/15/2022

While I strongly support standardized biopsy criteria, the criteria proposed is stringent and resource heavy. We have adopted a standardized biopsy policy internally that requires biopsy of all kidneys with KDPI >85%. Since the implementation of this simple policy, we have seen our renal discard rate decrease dramatically. This policy only caters to less aggressive transplant programs. Some OPOs, such as ours are now denying biopsy requests from these centers, and we are seeing increase in kidney utilization as a result. With the implementation of the CMS Collaboratives to increase kidney utilization and decrease discards, this suggested policy is counterintuitive. We would strongly support standardized acceptance criteria be implemented. Most centers slow the allocation process because each surgeon has different criteria.

Kevin Stump | 02/14/2022

As a former transplant coordinator, I view this proposal as counterintuitive to transplanting more people. In addition, this proposal seems to be counterproductive to the intent of the new CMS Kidney Collaborative. At the Mississippi Organ Recovery Agency we implemented a renal transplant task force to evaluate why kidneys were not being transplanted. This task force was created at the end of 2019 and based on our data we implemented a policy that we would only biopsy a kidney if the KDPI was greater than 85. Our kidney discard rate dropped from 15.7% to 8.6%. Part of our rationale for the creation of this policy was based on the data from papers published about biopsy utilization in Europe. It appears that kidney transplant programs in the United States use the kidney biopsy as another excuse to not transplant a kidney. If it pumps it transplants, is a good philosophy that would benefit more Americans. Kevin Stump CEO Mississippi Organ Recovery Agency

Parmjeet Randhawa | 02/10/2022

After I posted my comments yesterday, I came across a very pertinent article. It can be accessed using the DOI: 10.1038/s41379-021-00927-2 PMID 34584213 This article shows that, despite the expected pre-implantation frozen section discrepancies, arteriolar hyalinosis on frozen predicted graft loss. Arteriolar hyalinosis was as common as diabetic glomerulosclerosis, making a case that both lesions be scored. The authors provide another argument for not getting too hung up on frozen section artifacts: These biopsies can be optimally processed and examined post-transplant. Such examination can be can be utilized to perform even more accurate post-transplant risk stratification for deceased donor kidney from diabetic donors. The data collection form under revision now is not likely to be revised again for many more years. I see no downside in introducing arteriolar hyalinosis as an additional data point that could be captured. A simple suggested schema: 0: no arteriolar hyalinosis 1: mild or focal 2: transmural or circumferential The complete reference is as follows Aubre Gilbert 1, David Scott 2, Megan Stack 3, Angelo de Mattos 3, Doug Norman 3, Shehzad Rehman 3, Joseph Lockridge 3 4, David Woodland 2, Vanderlene Kung 1, Nicole K Andeen 5 Long-standing donor diabetes and pathologic findings are associated with shorter allograft survival in recipients of kidney transplants from diabetic donors. Mod Pathol . 2022 Jan;35(1):128-134.

Wes Aldred | 02/10/2022

Requiring biopsy for any history of diabetes seems unhelpful. This will require too many procurement biopsies and will lead to increased discard rates (which are likely inappropriate discards). The literature is fairly clear that procurement biopsies are fraught with errors: there is poor concordance between multiple procurement biopsies, procurement and reperfusion biopsies are often disconcordant, and have been its been shown that there is no association between histology and death censored graft survival.

Parmjeet Randhawa | 02/09/2022

KDPI does not incorporate biopsy findings. Therefore, restricting biopsies to KDPI>85 is not advisable. Artificial elevations of KDPI can occur for reversible creatinine, recent onset diabetes mellitus/hypertension (not long enough to damage the kidney), hepatitis C virus positivity (with no glomerulonephritis, which is a very uncommon complication), and just being African American (with no information on the ApoL1 status). Just as people age at different rates, so does the kidney. Biopsy for all donors >age 60 is reasonable. Certainly we need to educate the community more about not letting traditional criteria like 20% glomerulosclerosis lead to automatic discards. “Go/No go” decisions based on binary biopsy thresholds need to be replaced by biopsy findings being a part of the overall evaluation.

John Friedewald | 02/07/2022

I support this policy proposal and generally agree with the criteria established. One clinical scenario not addressed would be the donor with severe Acute Kidney Injury not meeting the definition of anuria or dialysis. In particular, I believe donors with concern for DIC and fibrin thrombi should be biopsied (these kidneys are often transplantable if the biopsy excludes significant evolving cortical necrosis). Depending on the timing of a donor OR, the donor may not have reached the need for dialysis and still have some UOP, but be headed in that direction. Thanks for the opportunity to comment on this important policy proposal. Uniformity in practice is all the more important with expanded distribution of kidneys and the need to for transplant centers to work with multiple OPOs.

Gregory Lynne | 01/30/2022

All kidneys should be tested and rated for SARS-COV2 antibody profiles. Differentiation should be specified or rated for naturally-acquired vs. mRNA-generated antibodies vs. a combination thereof. Recipients should be given access to said profiles at time of selection.