Donor hepatitis C antibody positivity misclassifies kidney donor profile index in non-hepatitis C-infected donors: time to revise the kidney donor profile index - a retrospective cohort study

How do we increase deceased donor kidney utilization and reduce discard?

PURPOSE OF REVIEW

This review aims to address the critical issue of expanding deceased donor kidney pool and reducing the discard rates of viable kidneys in the United States. It highlights advances in organ preservation techniques and explores strategies for expanding the donor pool by leveraging suboptimal and high-risk nonuse kidneys, including those affected by acute kidney injury (AKI), hepatitis C virus (HCV), and hepatitis B virus (HBV).

RECENT FINDINGS

Innovations in organ preservation, including hypothermic and normothermic machine perfusion, have demonstrated efficacy in improving outcomes for marginal and extended-criteria kidneys. The integration of normothermic regional perfusion (NRP) for donation after cardiac death (DCD) donors has enhanced organ utilization and graft viability. Additionally, research confirms that kidneys from AKI and HCV-positive donors, when managed with appropriate protocols, yield comparable long-term outcomes to standard transplants. Emerging data on HBV-positive donor kidneys further underscore their potential to safely expand transplant access with targeted antiviral prophylaxis.

SUMMARY

Optimizing deceased donor kidney utilization requires a multi-faceted approach, including advancements in preservation technologies, evidence-based decision-making for high-risk organs, and policy innovations. Leveraging these strategies can help address the growing organ shortage, enhance transplant outcomes, and ensure broader access to life-saving kidney transplants.

Risk of Cytomegalovirus Viremia Following Transplantation of Hepatitis C-Viremic Donor Kidneys Into Uninfected Recipients: A Multi-Center Retrospective Cohort Study

BACKGROUND

Several studies have suggested an increased risk of cytomegalovirus (CMV) viremia among Hepatitis C virus (HCV)-uninfected recipients of kidney transplants from HCV-RNA+ deceased donors (HCV D+/R-), but these studies featured small sample sizes and limited ability to address confounding variables.

METHODS

We assembled a retrospective cohort of adult kidney transplant recipients at five US centers between 4/1/2015 and 12/31/2020 to determine the association between HCV D+/R- transplants and the outcomes of CMV viremia (> 1000 IU/mL), death-censored graft failure, and mortality in the first posttransplant year compared to HCV D-/R- transplants. We generated highly similar matched cohorts of HCV D+/R- and HCV D-/R- recipients based on attributes that affect the risk of CMV viremia. We matched exactly on center, CMV donor/recipient serostatus, and antibody induction therapy.

RESULTS

The cohort comprised 275 HCV D+/R- recipients with a mean age of 52.5 years (SD = 10.7); 19% were CMV D+/R-, and 74% received anti-thymocyte globulin induction. With variable ratio matching, 267 HCV D+/R- recipients were matched to 996 HCV D-/R- recipients. CMV viremia occurred in 15% of HCV D+/R- and 11% of HCV D-R- recipients. In Cox regression, transplantation with an HCV-RNA+ donor kidney was not associated with a significantly higher risk of CMV viremia (HR 1.3, 95% CI 0.89-1.92) or death-censored graft loss (HR 0.61, 95% CI 0.31-1.2).

CONCLUSION

The risk of CMV viremia was not significantly increased among HCV D+/R- kidney recipients. Future studies should examine associations between donor-derived HCV infection and clinical outcomes of CMV syndrome and disease.

Outcomes of kidney, liver, and simultaneous liver and kidney transplants from hepatitis c infected donors to hepatitis c naïve recipients: A large single center experience

BACKGROUND

With the introduction of direct-acting antiviral therapies (DAAs), the non-use rate of hepatitis C virus (HCV)-positive donor organs (D+) has decreased significantly. We present the donor, recipient, and transplant allograft characteristics, along with recipient outcomes, in one of the largest cohorts of HCV-D+ transplants into HCV-naïve recipients (R-).

METHODS

Charts of HCV D+/R- kidney (KT), liver (LT), and simultaneous liver-kidney (SLKT) transplant recipients between January 2019 and July 2022 were reviewed. Primary outcomes of interest included waitlist times and 1-year graft failure. Secondary outcomes included hospital and intensive care unit length of stay, post-transplant complications, effectiveness of DAA therapy, and characteristics of patients who relapsed from initial DAA therapy.

RESULTS

Fifty-five HCV D+/R- transplants at our center [42 KT (26 nucleic acid testing positive [NAT+], 16 NAT-), 12 LT (eight NAT+, four NAT-), and one SLKT (NAT+)] had a median waitlist time of 69 days for KT, 87 days for LT, and 15 days for SLKT. There were no graft failures at 1 year. All viremic recipients were treated with a 12-week course of DAAs, of which 100% achieved end of treatment response (EOTR)-85.7% (n = 30) achieved sustained virologic response (SVR) and 14.3% relapsed (n = 5; four KT, one LT). All relapsed recipients were retreated and achieved SVR. The most common post-transplantation complications include BK virus infection (n = 9) for KT and non-allograft infections (n = 4) for LT.

CONCLUSIONS

Our study has demonstrated no graft failures or recipient deaths at 1 year, and despite a 14.3% relapse rate, we achieved 100% SVR. Complications rates of D+/R- appeared comparable to national D-/R- complication rates. Further studies comparing D+/R- to D-/R- outcomes are needed.

Kidney Transplantation in an Elderly Veteran Population With Hepatitis C Virus Nucleic Acid Test-Positive Donors Results in Improved Outcomes After Prophylactic Glecaprevir/Pibrentasvir Therapy

BACKGROUND

The average age of waitlisted veterans is 64. Recent data has shown the safety and benefits of using kidneys from hepatitis C virus nucleic acid test (HCV NAT)-positive donors. However, these studies were limited to younger patients with initiation of therapy after transplant. The aim of this study was to determine the safety and efficacy of a preemptive treatment protocol in an elderly veteran population.

METHODS

This was a prospective, open-label trial with 21 deceased donor kidney transplantations (DDKTs) with HCV NAT-positive kidneys and 32 DDKTs with HCV NAT-negative transplanted between November 2020 and March 2022. The HCV NAT-positive recipients were treated with once-daily glecaprevir/pibrentasvir started preoperatively and continued for 8 weeks. Sustained virologic response (SVR)12 was determined by negative NAT Student's t test. Other endpoints included patient and graft survival as well as graft function.

RESULTS

There was no major difference between the cohorts other than the increased number of donation after circulatory death kidneys in the non-HCV recipients. Post-transplant graft and patient outcomes were equivalent between the groups. Eight of the 21 HCV NAT-positive recipients had detectable HCV viral loads 1 day after transplant, but all were undetectable by day 7 with 100% SVR12. Calculated estimated glomerular filtration rate was improved in the HCV NAT-positive cohort at week 8 (58.26 vs 47.16 mL/min; P < .05) and continued to be improved over non-HCV recipients 1 year after transplant (71.38 vs 42.15 mL/min; P < .05). Immunologic risk stratification was similar in both cohorts.

CONCLUSION

The HCV NAT-positive transplants with a preemptive treatment protocol results in improved graft function with minimal to no complications in an elderly veteran population.

Kidney utility and futility

Changes in kidney allocation coupled with the COVID-19 pandemic have placed tremendous strain on current systems of organ distribution and logistics. Although the number of deceased donors continues to rise annually in the United States, the proportion of marginal deceased donors (MDDs) is disproportionately growing. Cold ischemia times and kidney discard rates are rising in part related to inadequate planning, resources, and shortages. Complexity in kidney allocation and distribution has contributed to this dilemma. Logistical issues and the ability to reperfuse the kidney within acceptable time constraints increasingly determine clinical decision-making for organ acceptance. We have a good understanding of the phenotype of "hard to place" MDD kidneys, yet continue to promote a "one size fits all" approach to organ allocation. Allocation and transportation systems need to be agile, mobile, and flexible in order to accommodate the expanding numbers of MDD organs. By identifying "hard to place" MDD kidneys early and implementing a "fast-track" or open offer policy to expedite placement, the utilization rate of MDDs would improve dramatically. Organ allocation and distribution based on location, motivation, and innovation must lead the way. In the absence of change, we are sacrificing utility for futility and discard rates will continue to escalate.

Utilization of HCV viremic donors in kidney transplantation: a chance or a threat?

Kidney transplantation is the treatment of choice in end-stage renal disease. The main issue which does not allow to utilize it fully is the number of organs available for transplant. Introduction of highly effective oral direct-acting antivirals (DAAs) to the treatment of chronic hepatitis C virus infection (HCV) enabled transplantation of HCV viremic organs to naive recipients. Despite an increasing number of reports on the satisfying effects of using HCV viremic organs, including kidneys, they are more often rejected than those from HCV negative donors. The main reason is the presence of HCV viremia and not the quality of the organ. The current state of knowledge points to the fact that a kidney transplant from an HCV nucleic acid testing positive (NAT+) donor to naive recipients is an effective and safe solution to the problem of the insufficient number of organs available for transplantation. It does not, however, allow to draw conclusions as to the long-term consequence of such an approach. This review analyzes the possibilities and limitations of the usage of HCV NAT + donor organs. Abbreviations: DAA: direct-acting antivirals; HCV: hepatitis C virus; NAT: nucleic acid testing; OPTN: Organ Procurement and Transplantation Network; KDIGO: Kidney Disease: Improving Global Outcomes; Ab: antigen; eGFR: estimated glomerular filtration rate; D: donor; R: recipient; CMV: cytomegalovirus; HBV: hepatitis B virus; UNOS: United Network for Organ Sharing; PHS: Public Health Service; EBR/GZR: elbasvir/grazoprevir; SVR: sustained virologic response; RAS: resistance-associated substitutions; SOF: soforbuvir; GLE/PIB: glecaprevir/pibrentasvir; ACR: acute cellular rejection; AR: acute rejection; DSA: donor-specific antibodies; KTR: kidney transplant recipients; AASLD: American Association for the Study of Liver Disease; IDSA: Infectious Diseases Society of America; PPI: proton pump inhibitors; CKD: chronic kidney disease; GN: glomerulonephritis; KAS: The Kidney Allocation system.

Curative Therapies for Hepatitis C Virus Infection in Patients with Kidney Disease

Through the discovery of direct-acting antiviral therapies over the last decade, hepatitis C virus (HCV) has been transformed from a highly morbid and potentially fatal chronic viral infection to a curable illness. HCV is common in patients with kidney disease, is a risk factor for progression of CKD, is associated with higher morbidity and mortality in patients receiving dialysis, and leads to worse allograft and patient outcomes in recipients of kidney transplants. Clinical trial and real-world data of direct-acting antivirals in patients with kidney disease demonstrate extremely high cure rates and favorable adverse event profiles. This review covers the transformative effects of curative HCV therapies on patients with kidney disease, including patients with CKD, ESKD, and those who have received a kidney transplant.

A review of kidney transplantation from HCV-viremic donors into HCV-negative recipients

The safety and efficacy of direct-acting antiviral therapies have allowed the transplantation of organs from hepatitis C virus (HCV)-viremic donors into uninfected recipients. This novel strategy contrasts with the previous standard-of-care practice of limiting the transplantation of HCV infected-donor organs to HCV-infected recipients, or all too often, discarding viable organs. In this review, we summarize the published literature about the safety and feasibility of transplanting organs from HCV-viremic donors, the challenges that hinder wider adoption of this strategy, and future research needs.