Maximizing Utilization of the Donor Pool by Appropriate Classification of Hepatitis C Antibody-Positive Donors

Abstract

The most significant issue facing solid organ transplantation (SOT) is the limited supply of donor organs. Expansion of the donor pool is needed to save more lives through SOT. Deceased donors with positive hepatitis C (HCV) serologic testing have been used inconsistently in the past due to concern for worse recipient outcomes and an inability to easily treat HCV in nonliver recipients (1). Prior to 2015, the United Network for Organ Sharing (UNOS) required only HCV antibody (Ab) testing on deceased donors. As a result, all deceased donors with a detectable HCV Ab were labeled as "HCV positive." However, HCV Ab-positivity may reflect active infection, spontaneously cleared infection, or treated infection (2). There are no published data demonstrating that donors with cleared or treated HCV pose any risk for HCV transmission (1,3,4). Further, HCV has not been considered a disease that reactivates in the setting of immunosuppression. HCV nucleic acid testing (NAT) is able to distinguish active infection from cleared or treated infection, and since 2015, HCV NAT testing has also been required for all deceased donors. Since that time, it has been argued that organs from HCV Ab-positive NAT-negative donors should be considered no different than HCV Ab-negative donors and be more broadly utilized for all patients (1).Armed with these data, Kling et al evaluated national data on deceased donors to evaluate utilization of organs by donor HCV Ab and NAT status, and the impact that increased use of HCV Ab-positive NAT-negative organs would have on the donor pool (5). Over a 1-year period between 2015 and 2016, the authors found that although the vast majority of UNOS deceased donors were both Ab-and NAT-negative, 1.8% were HCV Ab-positive NATnegative, and 4.2% were Ab-positive NAT-positive. Further, they found that the clinical characteristics of HCV Ab-positive NAT-negative donors were otherwise favorable for donation: they were young, suffered brain death, and had few medical comorbidities.To evaluate the magnitude of the unused organs from HCV Ab-positive NAT-negative donors, the authors developed a predictive model to determine the number of additional organs that would be available from these donors after adjusting for other factors that might impact organ utilization. They found that use of HCV Ab-positive NAT-negative donors could add 48 kidney donors, 37 heart donors, 15 lung donors, 9 pancreas donors, and 1 small bowel donor in a 1-year period. It would not expand the liver donor pool since HCV Ab-positive donors are already used for liver transplantation at a high rate. They also found that using Ab-positive NAT-positive donors would increase the donor pool notably; there is early documentation of success with this approach, though this is a more complex decision given the need to treat the recipient for HCV posttransplant (6).There are a few limitations of the described study. First, the use of UNOS data underestimates the true impact of adding HCV Ab-positive NAT-negative donors, since UNOS only counts deceased...

Population level outcomes and cost-effectiveness of hepatitis C treatment pre- vs postkidney transplantation

“…The reason to delay HCV therapy is to preserve a patient's option to accept an HCV‐viremic organ, and thereby accelerate transplantation. HCV‐viremic donors provide more than 800 kidneys per year to the deceased donor pool, and this contribution is projected to increase in light of the opioid epidemic affecting many parts of the United States . However, the magnitude of that benefit varies, as not all transplant centers utilize HCV‐viremic organs and many potential HCV‐infected donors are not pursued for organ donation.…”

Trends in utilization of deceased donor kidneys based on hepatitis C virus status and impact of public health service labeling on discard

“…A recent companion study also confirms similar or superior short‐term outcomes from transplantation with HCV+ kidneys . Hence, some authors even question the need for including HCV Ab result with donor offers and KDPI calculations and recommend uniform utilization of NAT status alone …”

“…21 Hence, some authors even question the need for including HCV Ab result with donor offers and KDPI calculations and recommend uniform utilization of NAT status alone. [39][40][41] Strengths of our study include a large sample size of a national data set. Limitations of our study include the following: (a) it is a retrospective registry data analysis without a control group; (b) the OPTN data set does not include information regarding potential donors in whom a donor consent was not obtained and not recovered for transplant; (c) missing data can introduce bias; (d) reporting delays and labeling errors might happen.…”

Center-level trends in utilization of HCV-exposed donors for HCV-uninfected kidney and liver transplant recipients in the United States

“…[1][2][3][4][5] In light of these factors and the persistent organ shortage, transplant centers have reported increasing willingness to use HCV Ab+ donors for HCV-uninfected (HCV-) recipients, and there is some evidence that this practice is growing. [18][19][20] Viremic donors, however, are more likely to transmit HCV: two pilot trials using HCV Ab+ viremic kidney donors for HCV-recipients found that 5 (50%) and 10 (100%) patients developed viremia. 15 One study using 32 HCV Ab+ aviremic kidney donors for HCV-recipients found no subsequent HCV viremia among recipients, whereas another study using 26 HCV Ab+ aviremic liver donors for HCV-recipients found HCV transmission in four (16%) patients.…”

“…16,17 Given the low risk of transmission and survival benefit of transplantation, some advocate using HCV Ab+ aviremic donors more broadly. [18][19][20] Viremic donors, however, are more likely to transmit HCV: two pilot trials using HCV Ab+ viremic kidney donors for HCV-recipients found that 5 (50%) and 10 (100%) patients developed viremia. 21,22 However, median time to transplant after trial enrollment was less than 2 months and all patients experienced HCV cure with DAA treatment.…”