MELD Exceptions and Rates of Waiting List Outcomes.

Model for End-stage Liver Disease (MELD)-based allocation of deceased donor livers allows exceptions for patients whose score may not reflect their true mortality risk. We hypothesized that organ procurement organizations (OPOs) may differ in exception practices, use of exceptions may be increasing over time, and exception patients may be advantaged relative to other patients. We analyzed longitudinal MELD score, exception and outcome in 88 981 adult liver candidates as reported to the United Network for Organ Sharing from 2002 to 2010. Proportion of patients receiving an HCC exception was 0-21.4% at the OPO-level and 11.9-18.8% at the region level; proportion receiving an exception for other conditions was 0.0%-13.1% (OPO-level) and 3.7-9.5 (region-level). Hepatocellular carcinoma (HCC) exceptions rose over time (10.5% in 2002 vs. 15.5% in 2008, HR = 1.09 per year, p<0.001) as did other exceptions (7.0% in 2002 vs. 13.5% in 2008, HR = 1.11, p<0.001). In the most recent era of HCC point assignment (since April 2005), both HCC and other exceptions were associated with decreased risk of waitlist mortality compared to nonexception patients with equivalent listing priority (multinomial logistic regression odds ratio [OR] = 0.47 for HCC, OR = 0.43 for other, p<0.001) and increased odds of transplant (OR = 1.65 for HCC, OR = 1.33 for other, p<0.001). Policy advantages patients with MELD exceptions; differing rates of exceptions by OPO may create, or reflect, geographic inequity.

The economic implications of broader sharing of liver allografts.

Liver transplantation has evolved over the past four decades into the most effective method to treat end-stage liver failure and one of the most expensive medical technologies available. Accurate understanding of the financial implication of recipient severity of illness is crucial to assessing the economic impact of allocation policies. A novel database of linked clinical data from the Organ Procurement and Transplantation Network with cost accounting data from the University HealthSystem Consortium was used to analyze liver transplant costs for 15,813 liver transplants. This data was then utilized to consider the economic impact of alternative allocation systems designed to increase sharing of liver allografts using simulation results. Transplant costs were strongly associated with recipient severity of illness as assessed by the MELD score (p < 0.0001); however, this relationship was not linear. Simulation analysis of the reallocation of livers from low MELD patients to high MELD using a two-tiered regional sharing approach (MELD 15/25) resulted in 88 fewer deaths annually at estimated cost of $17,056 per quality-adjusted life-year saved. The results suggest that broader sharing of liver allografts offers a cost-effective strategy to reduce the mortality from end stage liver disease.

The clinical importance of flow cytometry crossmatch in the context of CDC crossmatch results.

BACKGROUND: The complement-dependent microcytotoxicity crossmatch (CDCXM) is a standard method for evaluating the presence of preformed antibodies before transplantation. The flow cytometry crossmatch (FCXM) is more sensitive, but there is controversy regarding translation of its increased sensitivity to clinically relevant graft outcomes. METHODS: We analyzed Organ Procurement and Transplant Network registry data for living and deceased donor kidney transplants performed in 1995 to 2009 after both CDCXM and FCXM testing. Transplants with negative CDCXM (CDCXM(-)) and with T-cell positive (T(+)), T-cell negative/B-cell positive (T(-)B(+)), or T- and B-cell negative (T(-)B(-)) FCXM results were included. Graft survival according to crossmatch results was compared by survival analysis. RESULTS: Among patients transplanted with negative CDCXM (CDCXM(-)), deceased and living donor graft recipients with T(+) FXCM experienced significant absolute reductions in 5-year graft survival of 11.5% and 8.8% compared to those with T(-) FCXM (P < .0001). Compared to patients with FCXM(-)/CDCXM(-) deceased and living donor recipients with T(-)B(+) FCXM/CDCXM(-) had absolute reductions in 5-year graft survival of 9.6% and 7.6%, respectively (P < .0001). Upon multivariate adjustment with Cox regression, T(+) FCXM/CDCXM(-) deceased donor transplantation was associated with 51% higher adjusted relative risk of 1-year graft loss than FCXM(-)/CDCXM(-). Relative risks were more marked at 1 year for the T(+) groups but stronger in the 1- to 5-year interval for the T(-)B(+) groups. CONCLUSION: Positive FCXM has important prognostic implications even when CDCXM is negative. Thus, positive FCXM should not routinely be dismissed as "overly sensitive" when CDCXM is negative.