Reassessing the survival benefit of deceased donor liver transplantation: retrospective cohort study

Retransplantation in Living Donor Liver Transplantation

The need for retransplantation after living donor liver transplantation can occur early, mainly because of technical difficulties such as hepatic artery thrombosis or as a result of early allograft dysfunction as a symptom of small-for-size syndrome. Patients with autoimmune diseases may develop progressive graft failure from recurrent disease. The ethics of retransplantation can be complicated by the cause of the initial liver disease, which may be self-inflicted or the outcome of malignancy. This is especially true in countries without the availability of deceased donors for salvage, and a second living donor would be needed. Nevertheless, patients who experience early or late graft failure should be considered for retransplant if they are deemed acceptable candidates. When a living donor is required for retransplant, the equipoise between donor risk and autonomy and recipient outcome should be considered.

Transplant center variability in utilizing nonstandard donors and its impact on the transplantation of patients with lower MELD scores

There is a subset of patients with lower MELD scores who are at substantial risk of waitlist mortality. In order to transplant such patients, transplant centers must utilize "nonstandard" donors (eg, living donors, donation after circulatory death), which are traditionally offered to those patients who are not at the top of the waitlist. We used Organ Procurement and Transplantation data to evaluate center-level and region-level variability in the utilization of nonstandard donors and its impact on MELD at transplant among adult liver-alone non-status 1 patients transplanted from April 1, 2020, to September 30, 2022. The center-level variability in the utilization of nonstandard donors was 4-fold greater than the center-level variability in waitlisting practices (waitlistings with a MELD score of <20). While there was a moderate correlation between center-level waitlisting and transplantation of patients with a MELD score of <20 ( p = 0.58), there was a strong correlation between center-level utilization of nonstandard donors and center-level transplantation of patients with a MELD score of <20 ( p = 0.75). This strong correlation between center-level utilization of "nonstandard" donors and center-level transplantation of patients with a MELD score of <20 was limited to regions 2, 4, 5, 9, and 11. Transplant centers that utilize more nonstandard donors are more likely to successfully transplant patients at lower MELD scores. Public reporting of these data could benefit patients, caregivers, and referring providers, and be used to help maximize organ utilization.

Patient years lost due to cytomegalovirus serostatus mismatching in the scientific registry of transplant recipients

Background

The cytomegalovirus (CMV) mismatch rate in deceased donor kidney transplant (DDKT) recipients in the US remains above 40%. Since CMV mismatching is common in DDKT recipients, the cumulative effects may be significant in the context of overall patient and graft survival. Our primary objective was to describe the short- and long-term risks associated with high-risk CMV donor positive/recipient negative (D+/R-) mismatching among DDKT recipients with the explicit goal of deriving a mathematical mismatching penalty.

Methods

We conducted a retrospective, secondary analysis of the Scientific Registry of Transplant Recipients (SRTR) database using donor-matched DDKT recipient pairs (N=105,608) transplanted between 2011-2022. All-cause mortality and graft failure hazard ratios were calculated from one year to ten years post-DDKT. All-cause graft failure included death events. Survival curves were calculated using the Kaplan-Meier estimation at 10 years post-DDKT and extrapolated to 20 years to provide the average graft days lost (aGDL) and average patient days lost (aPDL) due to CMV D+/R- serostatus mismatching. We also performed an age-based stratification analysis to compare the relative risk of CMV D+ mismatching by age.

Results

Among 31,518 CMV D+/R- recipients, at 1 year post-DDKT, the relative risk of death increased by 29% (p<0.001), and graft failure increased by 17% (p<0.001) as compared to matched CMV D+/R+ group (N=31,518). Age stratification demonstrated a significant increase in the risk associated with CMV mismatching in patients 40 years of age and greater. The aGDL per patient due to mismatching was 125 days and the aPDL per patient was 100 days.

Conclusion

The risks of CMV D+/R- mismatching are seen both at 1 year post-DDKT period and accumulated throughout the lifespan of the patient, with the average CMV D+/R- recipient losing more than three months of post-DDKT survival time. CMV D+/R- mismatching poses a more significant risk and a greater health burden than previously reported, thus obviating the need for better preventive strategies including CMV serodirected organ allocation to prolong lifespans and graft survival in high-risk patients.