Discovered cancers at postmortem donor examination: A starting point for quality improvement of donor assessment

BACKGROUND

clinical and imaging investigations allow a detailed assessment of an organ donor, but a quota of cancer still elude detection. Complete autopsy of donors is even less frequently performed, due to economic issues and increasing availability of high-quality imaging. The aim of this study is to gather evidence from the literature on donor malignancy discovered at autopsy following organ donation and to discuss the utility and limitations of autopsy practice in the field of transplantation.

METHODS

A systematic search according to PRISMA guidelines was carried out in Pubmed and Embase databases until September 2020 to select articles with reporting of cancer discovered in a donor at postmortem examination. Cancer discover in not-transplant setting were excluded. A descriptive synthesis was provided.

RESULTS

Of 7388 articles after duplicates removal, 56 were included. Fifty-one studies reported on complete autopsy, while 5 dealt only with limited autopsy (prostate and central nervous system). The number of autopsies ranged between 1 and 246 with a total of 823 autopsies performed. The most frequent cancer discovered at autopsy was lymphoma (n = 13, 15%), followed by renal cell carcinoma (RCC) (n = 11, 13%), non-small cell lung cancer (NSCLC) (n = 10, 11%), melanoma (n = 10, 11%), choriocarcinoma (n = 6, 7%) and glioblastoma (GBM) (n = 6, 7%).

CONCLUSIONS

Lymphoma and melanoma are still difficult-to-detect cancers both during donor investigation and at procurement, whilst prostate cancer and choriocarcinoma are almost always easily detected nowadays thank to blood markers and clinical examination. There have been improvements with time in pre-donation detection procedures which are now working well, particularly when complete imaging investigations are performed, given that detection rate of CT/MRI is high and accurate. Autopsy can play a role to help to establish the correct donor management pathways in case of cancer discover. Furthermore, it helps to better understand which cancers are still eluding detection and consequently to refine guidelines' assessment procedures.

Donor-transmitted cancer in kidney transplant recipients: a systematic review

The transmission of cancer from a donor organ is a rare event but has important consequences. Aim of this systematic review was to summarize all the published evidence on cancer transmission in kidney recipients. We reviewed published case reports and series describing the outcome of recipients with donor-transmitted cancer until August 2019. A total of 128 papers were included, representing 234 recipients. The most common transmitted cancers were lymphoma (n = 48, 20.5%), renal cancer (42, 17.9%), melanoma (40, 17.1%), non-small cell lung cancer (n = 13, 5.6%), neuroendocrine cancers comprising small cell lung cancer (n = 11, 4.7%) and choriocarcinoma (n = 10, 4.3%). There was a relative lack of glioblastoma and gastrointestinal cancers with only 6 and 5 cases, respectively. Melanoma and lung cancer had the worst prognosis, with 5-years overall survival of 43% and 19%, respectively; while renal cell cancer and lymphomas had a favorable prognosis with 5-years overall survival of 93 and 63%, respectively. Metastasis of cancer outside the graft was the most important adverse prognostic factor. Overall reporting was good, but information on donors' cause of death and investigations at procurement was often lacking. Epidemiology of transmitted cancer has evolved, thanks to screening with imaging and blood tests, as choriocarcinoma transmission have almost abolished, while melanoma and lymphoma are still difficult to detect and prevent.

Antibody-mediated rejection: New approaches in prevention and management

Despite the success of desensitization protocols, antibody-mediated rejection (AMR) remains a significant contributor to renal allograft failure in patients with donor-specific antibodies. Plasmapheresis and high-dose intravenous immunoglobulin have proved to be effective treatments to prevent and treat AMR, but irreversible injury in the form of transplant glomerulopathy can commonly manifest months to years later. There is an unmet need to improve the outcomes for patients at risk for AMR. Updated Banff criteria now take into account the increasing understanding of the complex and heterogeneous nature of AMR phenotypes, including the timing of rejection, subclinical and chronic AMR, C4d-negative AMR, and antibody-mediated vascular rejection. Treatment for AMR is not standardized, and there is little in the way of evidence-based treatment guidelines. Refining more precisely the mechanisms of injury responsible for different AMR phenotypes and establishing relevant surrogate endpoints to facilitate more informative studies will likely allow for more accurate determination of prognosis and efficacious intervention using new therapeutic approaches. In addition to plasma exchange and intravenous immunoglobulin, a number of other add-on therapies have been tried in small studies without consistent benefit, including anti-CD20, proteasome inhibitors, complement inhibitors, anti-interleukin-6 receptor blockers, and immunoglobulin G-degrading enzyme of Streptococcus pyogenes (called IdeS).

Impact of Protease Inhibitor-Based Anti-Retroviral Therapy on Outcomes for HIV+ Kidney Transplant Recipients

Excellent outcomes have been demonstrated among select HIV-positive kidney transplant (KT) recipients with well-controlled infection, but to date, no national study has explored outcomes among HIV+ KT recipients by antiretroviral therapy (ART) regimen. Intercontinental Marketing Services (IMS) pharmacy fills (1/1/01-10/1/12) were linked with Scientific Registry of Transplant Recipients (SRTR) data. A total of 332 recipients with pre- and posttransplantation fills were characterized by ART at the time of transplantation as protease inhibitor (PI) or non-PI-based ART (88 PI vs. 244 non-PI). Cox proportional hazards models were adjusted for recipient and donor characteristics. Comparing recipients by ART regimen, there were no significant differences in age, race, or HCV status. Recipients on PI-based regimens were significantly more likely to have an Estimated Post Transplant Survival (EPTS) score of >20% (70.9% vs. 56.3%, p = 0.02) than those on non-PI regimens. On adjusted analyses, PI-based regimens were associated with a 1.8-fold increased risk of allograft loss (adjusted hazard ratio [aHR] 1.84, 95% confidence interval [CI] 1.22-2.77, p = 0.003), with the greatest risk observed in the first posttransplantation year (aHR 4.48, 95% CI 1.75-11.48, p = 0.002), and a 1.9-fold increased risk of death as compared to non-PI regimens (aHR 1.91, 95% CI 1.02-3.59, p = 0.05). These results suggest that whenever possible, recipients should be converted to a non-PI regimen prior to kidney transplantation.

The National Landscape of Living Kidney Donor Follow-Up in the United States

In 2013, the Organ Procurement and Transplantation Network (OPTN)/ United Network for Organ Sharing (UNOS) mandated that transplant centers collect data on living kidney donors (LKDs) at 6 months, 1 year, and 2 years postdonation, with policy-defined thresholds for the proportion of complete living donor follow-up (LDF) data submitted in a timely manner (60 days before or after the expected visit date). While mandated, it was unclear how centers across the country would perform in meeting thresholds, given potential donor and center-level challenges of LDF. To better understand the impact of this policy, we studied Scientific Registry of Transplant Recipients data for 31,615 LKDs between January 2010 and June 2015, comparing proportions of complete and timely LDF form submissions before and after policy implementation. We also used multilevel logistic regression to assess donor- and center-level characteristics associated with complete and timely LDF submissions. Complete and timely 2-year LDF increased from 33% prepolicy (January 2010 through January 2013) to 54% postpolicy (February 2013 through June 2015) (p < 0.001). In an adjusted model, the odds of 2-year LDF increased by 22% per year prepolicy (p < 0.001) and 23% per year postpolicy (p < 0.001). Despite these annual increases in LDF, only 43% (87/202) of centers met the OPTN/UNOS-required 6-month, 1-year, and 2-year LDF thresholds for LKDs who donated in 2013. These findings motivate further evaluation of LDF barriers and the optimal approaches to capturing outcomes after living donation.

The Incremental Cost of Incompatible Living Donor Kidney Transplantation: A National Cohort Analysis

Incompatible living donor kidney transplantation (ILDKT) has been established as an effective option for end-stage renal disease patients with willing but HLA-incompatible living donors, reducing mortality and improving quality of life. Depending on antibody titer, ILDKT can require highly resource-intensive procedures, including intravenous immunoglobulin, plasma exchange, and/or cell-depleting antibody treatment, as well as protocol biopsies and donor-specific antibody testing. This study sought to compare the cost and Medicare reimbursement, exclusive of organ acquisition payment, for ILDKT (n = 926) with varying antibody titers to matched compatible transplants (n = 2762) performed between 2002 and 2011. Data were assembled from a national cohort study of ILDKT and a unique data set linking hospital cost accounting data and Medicare claims. ILDKT was more expensive than matched compatible transplantation, ranging from 20% higher adjusted costs for positive on Luminex assay but negative flow cytometric crossmatch, 26% higher for positive flow cytometric crossmatch but negative cytotoxic crossmatch, and 39% higher for positive cytotoxic crossmatch (p < 0.0001 for all). ILDKT was associated with longer median length of stay (12.9 vs. 7.8 days), higher Medicare payments ($91 330 vs. $63 782 p < 0.0001), and greater outlier payments. In conclusion, ILDKT increases the cost of and payments for kidney transplantation.

PROviding Better ACcess To ORgans: A comprehensive overview of organ-access initiatives from the ASTS PROACTOR Task Force

The American Society of Transplant Surgeons (ASTS) PROviding better Access To Organs (PROACTOR) Task Force was created to inform ongoing ASTS organ access efforts. Task force members were charged with comprehensively cataloguing current organ access activities and organizing them according to stakeholder type. This white paper summarizes the task force findings and makes recommendations for future ASTS organ access initiatives.

Predonation Prescription Opioid Use: A Novel Risk Factor for Readmission After Living Kidney Donation

Implications of opioid use in living kidney donors for key outcomes, including readmission rates after nephrectomy, are unknown. We integrated Scientific Registry of Transplant Recipients data with records from a nationwide pharmacy claims warehouse and administrative records from an academic hospital consortium to quantify predonation prescription opioid use and postdonation readmission events. Associations of predonation opioid use (adjusted odds ratio [aOR]) in the year before donation and other baseline clinical, procedural, and center factors with readmission within 90 days postdonation were examined by using multivariate logistic regression. Among 14 959 living donors, 11.3% filled one or more opioid prescriptions in the year before donation. Donors with the highest level of predonation opioid use (>305 mg/year) were more than twice as likely as nonusers to be readmitted (6.8% vs. 2.6%; aOR 2.49, 95% confidence interval 1.74-3.58). Adjusted readmission risk was also significantly (p < 0.05) higher for women (aOR = 1.25), African Americans (aOR = 1.45), spouses (aOR = 1.42), exchange participants (aOR = 1.46), uninsured donors (aOR = 1.40), donors with predonation estimated glomerular filtration rate <60 mL/min/1.73 m² (aOR = 2.68), donors with predonation pulmonary conditions (aOR = 1.54), and after robotic nephrectomy (aOR = 1.68). Predonation opioid use is independently associated with readmission after donor nephrectomy. Future research should examine underlying mechanisms and approaches to reducing risks of postdonation complications.

A Smartphone App for Increasing Live Organ Donation

The incidence of live donor transplantation has declined over the past decade, and waitlisted candidates report substantial barriers to identifying a live donor. Since asking someone to donate feels awkward and unfamiliar, candidates are hesitant to ask directly and may be more comfortable with a passive approach. In collaboration with Facebook leadership (Facebook Inc., Menlo Park, CA), we developed a mobile application-an app-that enables waitlisted candidates to create a Facebook post about their experience with organ failure and their need for a live donor. We conducted a single-center prospective cohort study of 54 adult kidney-only and liver-only waitlisted candidates using the Facebook app. Cox proportional hazards models were used to describe donor referral on behalf of candidates using the app compared with matched controls. The majority of candidates who used the app reported it to be "good" or "excellent" with regard to the installation process (82.9%), readability (88.6%), simplicity (70.6%), clarity (87.5%) and the information provided (85.3%). Compared with controls, candidates using the Facebook app were _2.43 6.61_17.98 times more likely to have a donor come forward on their behalf (p < 0.001). The Facebook app is an easy-to-use instrument that enables waitlisted candidates to passively communicate with their social network about their need for a live donor.

Splenic Irradiation for the Treatment of Severe Antibody-Mediated Rejection

Patients requiring desensitization prior to renal transplantation are at risk for developing severe antibody-mediated rejection (AMR) refractory to treatment with plasmapheresis and intravenous immunoglobulin (PP/IVIg). We have previously reported success at graft salvage, long-term graft survival and protection against transplant glomerulopathy with the use of eculizumab and splenectomy in addition to PP/IVIg. Splenectomy may be an important component of this combination therapy and is itself associated with a marked reduction in donor-specific antibody (DSA) production. However, splenectomy represents a major operation, and some patients with severe AMR have comorbid conditions that substantially increase their risk of complications during and after surgery. In an effort to spare recipients the morbidity of a second operation, we used splenic irradiation in lieu of splenectomy in two incompatible live donor kidney transplant recipients with severe AMR in addition to PP/IVIg, rituximab and eculizumab. This novel approach to the treatment of severe AMR was associated with allograft salvage, excellent graft function and no short- or medium-term adverse effects of the radiation therapy. One-year surveillance biopsies did not show transplant glomerulopathy (tg) on light microscopy, but microcirculation inflammation and tg were present on electron microscopy.

Effects of High-Risk Kidneys on Scientific Registry of Transplant Recipients Program Quality Reports

There is a perception that transplanting high-risk kidneys causes programs to be identified as underperforming, thereby increasing the frequency of discards and diminishing access to transplant. Thus, the Organ Procurement and Transplantation Network (OPTN) has considered excluding transplants using kidneys from donors with high Kidney Donor Profile Index (KDPI) scores (≥0.85) when assessing program performance. We examined whether accepting high-risk kidneys (KDPI ≥0.85) for transplant yields worse outcome evaluations. Despite a clear relationship between KDPI and graft failure and mortality, there was no relationship between a program's use of high-KDPI kidneys and poor performance evaluations after risk adjustment. Excluding high-KDPI donor transplants from the June 2015 evaluations did not alter the programs identified as underperforming, because in every case underperforming programs also had worse-than-expected outcomes among lower-risk donor transplants. Finally, we found that hypothetically accepting and transplanting additional kidneys with KDPI similar to that of kidneys currently discarded would not adversely affect program evaluations. Based on the study findings, there is no evidence that programs that accept higher-KDPI kidneys are at greater risk for low performance evaluations, and risk aversion may limit access to transplant for candidates while providing no measurable benefit to program evaluations.

A Risk Index for Living Donor Kidney Transplantation

Choosing between multiple living kidney donors, or evaluating offers in kidney paired donation, can be challenging because no metric currently exists for living donor quality. Furthermore, some deceased donor (DD) kidneys can result in better outcomes than some living donor kidneys, yet there is no way to compare them on the same scale. To better inform clinical decision-making, we created a living kidney donor profile index (LKDPI) on the same scale as the DD KDPI, using Cox regression and adjusting for recipient characteristics. Donor age over 50 (hazard ratio [HR] per 10 years = 1.15 1.241.33 ), elevated BMI (HR per 10 units = 1.01 1.091.16 ), African-American race (HR = 1.15 1.251.37 ), cigarette use (HR = 1.09 1.161.23 ), as well as ABO incompatibility (HR = 1.03 1.271.58 ), HLA B (HR = 1.03 1.081.14 ) mismatches, and DR (HR = 1.04 1.091.15 ) mismatches were associated with greater risk of graft loss after living donor transplantation (all p < 0.05). Median (interquartile range) LKDPI score was 13 (1-27); 24.2% of donors had LKDPI < 0 (less risk than any DD kidney), and 4.4% of donors had LKDPI > 50 (more risk than the median DD kidney). The LKDPI is a useful tool for comparing living donor kidneys to each other and to deceased donor kidneys.

Perioperative Complications After Living Kidney Donation: A National Study

We integrated the US transplant registry with administrative records from an academic hospital consortium (97 centers, 2008-2012) to identify predonation comorbidity and perioperative complications captured in diagnostic, procedure, and registry sources. Correlates (adjusted odds ratio, aOR) of perioperative complications were examined with multivariate logistic regression. Among 14 964 living kidney donors, 11.6% were African American. Nephrectomies were predominantly laparoscopic (93.8%); 2.4% were robotic and 3.7% were planned open procedures. Overall, 16.8% of donors experienced a perioperative complication, most commonly gastrointestinal (4.4%), bleeding (3.0%), respiratory (2.5%), surgical/anesthesia-related injuries (2.4%), and "other" complications (6.6%). Major Clavien Classification of Surgical Complications grade IV or higher affected 2.5% of donors. After adjustment for demographic, clinical (including comorbidities), procedure, and center factors, African Americans had increased risk of any complication (aOR 1.26, p = 0.001) and of Clavien grade II or higher (aOR 1.39, p = 0.0002), grade III or higher (aOR 1.56, p < 0.0001), and grade IV or higher (aOR 1.56, p = 0.004) events. Other significant correlates of Clavien grade IV or higher events included obesity (aOR 1.55, p = 0.0005), predonation hematologic (aOR 2.78, p = 0.0002) and psychiatric (aOR 1.45, p = 0.04) conditions, and robotic nephrectomy (aOR 2.07, p = 0.002), while annual center volume >50 (aOR 0.55, p < 0.0001) was associated with lower risk. Complications after live donor nephrectomy vary with baseline demographic, clinical, procedure, and center factors, but the most serious complications are infrequent. Future work should examine underlying mechanisms and approaches to minimizing the risk of perioperative complications in all donors.

Variation in Comedication Use According to Kidney Transplant Immunosuppressive Regimens: Application of Integrated Registry and Pharmacy Claims Data

BACKGROUND

Modern immunosuppression therapies (ISx) have many side effects, and transplant recipients must take an array of "comedications" to help mitigate complications. Comedication use patterns are not well described in large, representative samples because of lack of data.

METHODS

We integrated national U.S. transplant registry data with pharmacy records (2005-2010) from a large pharmaceutical claims clearinghouse to examine treatments for anemia, metabolic disorders, and infections in relation to ISx regimens in months 6-12 post-transplantation (N = 22,453). Associations of ISx with comedication use (adjusted odds ratio [aOR]) were quantified with multivariate logistic regression including adjustment for recipient, donor, and transplant factors.

RESULTS

Compared to a reference regimen of tacrolimus, mycophenolic acid, and prednisone, sirolimus-based ISx was associated with significantly more common use of erythropoiesis-stimulating agents (aOR 2.52, 95% confidence interval [CI] 2.06-3.09), iron (aOR 2.26, 95% CI 1.92-2.65), statins (aOR 1.47, 95% CI 1.33-1.63), fibrates (aOR 2.35, 95% CI 1.90-2.90), and phosphorous binders (aOR 2.85, 95% CI 1.80-4.50). Patterns were similar after adjustment for first-year estimated glomerular filtration rate, except the association with phosphorous binders was no longer significant. Cyclosporine-based ISx was associated with more common erythropoiesis-stimulating agent use, including after estimated glomerular filtration rate adjustment (aOR 1.61, 95% CI 1.24-2.10). Compared to those who were being administered triple ISx, recipients receiving tacrolimus-based dual and monotherapies had lower use of statins, angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (ACEi/ARBs), and antibacterial agents. Recipients of steroid-free ISx were less commonly treated for post-transplantation diabetes.

CONCLUSIONS

Alternate ISx regimens are associated with varying treatment requirements for hematologic, metabolic. and infectious complications. Comedication use should be considered in the cost-effectiveness and individualization of ISx regimens.

The Impact of Redistricting Proposals on Health Care Expenditures for Liver Transplant Candidates and Recipients

Redistricting, which means sharing organs in novel districts developed through mathematical optimization, has been proposed to reduce pervasive geographic disparities in access to liver transplantation. The economic impact of redistricting was evaluated with two distinct data sources, Medicare claims and the University HealthSystem Consortium (UHC). We estimated total Medicare payments under (i) the current allocation system (Share 35), (ii) full regional sharing, (iii) an eight-district plan, and (iv) a four-district plan for a simulated population of patients listed for liver transplant over 5 years, using the liver simulated allocation model. The model predicted 5-year transplant volumes (Share 35, 29,267; regional sharing, 29,005; eight districts, 29,034; four districts, 28,265) and a reduction in overall mortality, including listed and posttransplant patients, of up to 676 lives. Compared with current allocation, the eight-district plan was estimated to reduce payments for pretransplant care ($1638 million to $1506 million, p < 0.001), transplant episode ($5607 million to $5569 million, p < 0.03) and posttransplant care ($479 million to $488 million, p < 0.001). The eight-district plan was estimated to increase per-patient transportation costs for organs ($8988 to $11,874 per patient, p < 0.001) and UHC estimated hospital costs ($4699 per case). In summary, redistricting appears to be potentially cost saving for the health care system but will increase the cost of performing liver transplants for some transplant centers.

Extraction Time of Kidneys From Deceased Donors and Impact on Outcomes

Cold ischemia time (from flush to out-of-ice) and warm ischemia time (from out-of-ice to reperfusion) are known to impact delayed graft function (DGF) rates and long-term allograft survival following deceased donor kidney transplantation. We propose an additional ischemia time, extraction time, beginning with aortic cross-clamp and perfusion/cooling of the kidneys, and ending with removal of the kidneys and placement on ice on the backtable. During this time the kidneys rewarm, suffering an additional ischemic insult, which may impair transplant function. We measured extraction times of 576 kidneys recovered and transplanted locally between January 2006 and December 2008, then linked to Scientific Registry of Transplant Recipients (SRTR) data for outcomes. Extraction time ranged from 14 to 123 min, with a mean of 44.7 min. In SRTR-adjusted analyses, longer extraction time and DGF were statistically associated (odds ratio [OR] = 1.19 per 5 min beyond 60 min, 95% confidence interval [CI] 1.02-1.39, p = 0.03). Up to 60 min of extraction time, DGF incidence was 27.8%; by 120 min it doubled to nearly 60%. Although not statistically significant (OR = 1.19, 95% CI 0.96-1.49, p = 0.11), primary nonfunction rate also rose dramatically to nearly 20% by 120 min extraction time. Extraction time is a novel and important factor to consider when evaluating a deceased donor kidney offer and when strategizing personnel for kidney recovery.

Frailty and Health-Related Quality of Life in End Stage Renal Disease Patients of All Ages

BACKGROUND: Frailty is associated with worse health-related quality of life (HRQOL) in older adults and worse clinical outcomes in adults of all ages with end stage renal disease (ESRD). It is unclear whether frail adults of all ages with ESRD are more likely to experience worse HRQOL. OBJECTIVE: The goal of this study was to identify factors associated with worsening HRQOL in this population. DESIGN, SETTING AND MEASUREMENTS: We studied 233 adults of all ages with ESRD enrolled (11/2009-11/2013) in a longitudinal cohort study. Frailty status was measured at enrollment and HRQOL was reported (Excellent, Very Good, Good, Fair or Poor) at the initial assessment and follow-up (median follow-up 9.4 months). We studied factors associated with Fair/Poor HRQOL at follow-up using logistic regression and factors associated with HRQOL change using multinomial regression. All models were adjusted for age, sex, race, education, BMI, diabetes status, history of a previous transplant, type of dialysis and time between assessments. RESULTS: Fair/Poor HRQOL was reported by 28% at initial assessment and 33% at follow-up. 47.2% of participants had stable HRQOL, 22.8% better HRQOL, and 30.0% worse HRQOL at follow-up (P<0.001). In adjusted models, only frailty was associated with Fair/Poor HRQOL at follow-up (OR: 2.79, 95% CI: 1.32-5.90) and worsening HRQOL at follow-up (RR: 2.91, 95%CI: 1.08-7.80). CONCLUSIONS: Frail adults of all ages with ESRD are more likely to experience fair/poor HRQOL and worsening HRQOL over time. Frailty represents a state of decreased physiologic reserve that impacts not only clinical outcomes but also the patient-centered outcome of HRQOL.

Challenges and Clinical Decision-Making in HIV-to-HIV Transplantation: Insights From the HIV Literature

Life expectancy among HIV-infected (HIV+) individuals has improved dramatically with effective antiretroviral therapy. Consequently, chronic diseases such as end-stage liver and kidney disease are growing causes of morbidity and mortality. HIV+ individuals can have excellent outcomes after solid organ transplantation, and the need for transplantation in this population is increasing. However, there is a significant organ shortage, and HIV+ individuals experience higher mortality rates on transplant waitlists. In South Africa, the use of organs from HIV+ deceased donors (HIVDD) has been successful, but until recently federal law prohibited this practice in the United States. With the recognition that organs from HIVDD could fill a critical need, the HIV Organ Policy Equity (HOPE) Act was passed in November 2013, reversing the federal ban on the use of HIV+ donors for HIV+ recipients. In translating this policy into practice, the biologic risks of using HIV+ donors need to be carefully considered. In this mini-review, we explore relevant aspects of HIV virology, antiretroviral treatment, drug resistance, opportunistic infections and HIV-related organ dysfunction that are critical to a transplant team considering HIV-to-HIV transplantation.

Early changes in liver distribution following implementation of Share 35

In June 2013, a change to the liver waitlist priority algorithm was implemented. Under Share 35, regional candidates with MELD ≥ 35 receive higher priority than local candidates with MELD < 35. We compared liver distribution and mortality in the first 12 months of Share 35 to an equivalent time period before. Under Share 35, new listings with MELD ≥ 35 increased slightly from 752 (9.2% of listings) to 820 (9.7%, p = 0.3), but the proportion of deceased-donor liver transplants (DDLTs) allocated to recipients with MELD ≥ 35 increased from 23.1% to 30.1% (p < 0.001). The proportion of regional shares increased from 18.9% to 30.4% (p < 0.001). Sharing of exports was less clustered among a handful of centers (Gini coefficient decreased from 0.49 to 0.34), but there was no evidence of change in CIT (p = 0.8). Total adult DDLT volume increased from 4133 to 4369, and adjusted odds of discard decreased by 14% (p = 0.03). Waitlist mortality decreased by 30% among patients with baseline MELD > 30 (SHR = 0.70, p < 0.001) with no change for patients with lower baseline MELD (p = 0.9). Posttransplant length-of-stay (p = 0.2) and posttransplant mortality (p = 0.9) remained unchanged. In the first 12 months, Share 35 was associated with more transplants, fewer discards, and lower waitlist mortality, but not at the expense of CIT or early posttransplant outcomes.

Loss of pediatric kidney grafts during the "high-risk age window": insights from pediatric liver and simultaneous liver-kidney recipients

Pediatric kidney transplant recipients experience a high-risk age window of increased graft loss during late adolescence and early adulthood that has been attributed primarily to sociobehavioral mechanisms such as nonadherence. An examination of how this age window affects recipients of other organs may inform the extent to which sociobehavioral mechanisms are to blame or whether kidney-specific biologic mechanisms may also exist. Graft loss risk across current recipient age was compared between pediatric kidney (n = 17,446), liver (n = 12,161) and simultaneous liver-kidney (n = 224) transplants using piecewise-constant hazard rate models. Kidney graft loss during late adolescence and early adulthood (ages 17-24 years) was significantly greater than during ages <17 (aHR = 1.79, 95%CI = 1.69-1.90, p < 0.001) and ages >24 (aHR = 1.11, 95%CI = 1.03-1.20, p = 0.005). In contrast, liver graft loss during ages 17-24 was no different than during ages <17 (aHR = 1.03, 95%CI = 0.92-1.16, p = 0.6) or ages >24 (aHR = 1.18, 95%CI = 0.98-1.42, p = 0.1). In simultaneous liver-kidney recipients, a trend towards increased kidney compared to liver graft loss was observed during ages 17-24 years. Late adolescence and early adulthood are less detrimental to pediatric liver grafts compared to kidney grafts, suggesting that sociobehavioral mechanisms alone may be insufficient to create the high-risk age window and that additional biologic mechanisms may also be required.

Sirolimus use and cancer incidence among US kidney transplant recipients

Sirolimus has anti-carcinogenic properties and can be included in maintenance immunosuppressive therapy following kidney transplantation. We investigated sirolimus effects on cancer incidence among kidney recipients. The US transplant registry was linked with 15 population-based cancer registries and national pharmacy claims. Recipients contributed sirolimus-exposed time when sirolimus claims were filled, and unexposed time when other immunosuppressant claims were filled without sirolimus. Cox regression was used to estimate associations with overall and specific cancer incidence, excluding nonmelanoma skin cancers (not captured in cancer registries). We included 32,604 kidney transplants (5687 sirolimus-exposed). Overall, cancer incidence was suggestively lower during sirolimus use (hazard ratio [HR] = 0.88, 95% confidence interval [CI] = 0.70-1.11). Prostate cancer incidence was higher during sirolimus use (HR = 1.86, 95% CI = 1.15-3.02). Incidence of other cancers was similar or lower with sirolimus use, with a 26% decrease overall (HR = 0.74, 95% CI = 0.57-0.96, excluding prostate cancer). Results were similar after adjustment for demographic and clinical characteristics. This modest association does not provide strong evidence that sirolimus prevents posttransplant cancer, but it may be advantageous among kidney recipients with high cancer risk. Increased prostate cancer diagnoses may result from sirolimus effects on screen detection.

Variation in biliary complication rates following liver transplantation: implications for cost and outcome

Although biliary complications (BCs) have a significant impact on the outcome of liver transplantation (LT), variation in BC rates among transplant centers has not been previously analyzed. BC rate, LT outcome and spending were assessed using linked Scientific Registry of Transplant Recipients and Medicare claims (n = 16,286 LTs). Transplant centers were assigned to BC quartiles based upon risk-adjusted observed to expected (O:E) ratio of BC separately for donation after brain death (DBD) and donation after cardiac death (DCD) donors. The median incidence of BC was 300% greater in the highest versus lowest DBD quartiles (19.0% vs. 5.9%) and varied 250% between DCD quartiles (20.3%-8.4%). Donor and recipient characteristics suggest that high BC centers actually used lower donor risk index organs, fewer split livers and fewer imports (p < 0.001 for all). Transplant at a center in the highest O:E quartile was associated with increased posttransplant mortality (adjusted hazard ratio [aHR] 2.53, p = 0.007) in DCD transplant and increased graft loss (aHR 1.21, p = 0.02) in DBD transplant. Medicare spending was $22,895 (p < 0.0001) higher at centers in highest versus lowest BC quartile. In summary, BC rates vary widely among transplant centers and higher rates are a marker for an increased risk of death, graft failure and health-care spending.

Survival benefit of primary deceased donor transplantation with high-KDPI kidneys

The Kidney Donor Profile Index (KDPI) has been introduced as an aid to evaluating deceased donor kidney offers, but the relative benefit of high-KDPI kidney transplantation (KT) versus the clinical alternative (remaining on the waitlist until receipt of a lower KDPI kidney) remains unknown. Using time-dependent Cox regression, we evaluated the mortality risk associated with high-KDPI KT (KDPI 71-80, 81-90 or 91-100) versus a conservative, lower KDPI approach (remain on waitlist until receipt of KT with KDPI 0-70, 0-80 or 0-90) in first-time adult registrants, adjusting for candidate characteristics. High-KDPI KT was associated with increased short-term but decreased long-term mortality risk. Recipients of KDPI 71-80 KT, KDPI 81-90 KT and KDPI 91-100 KT reached a "break-even point" of cumulative survival at 7.7, 18.0 and 19.8 months post-KT, respectively, and had a survival benefit thereafter. Cumulative survival at 5 years was better in all three high-KDPI groups than the conservative approach (p < 0.01 for each comparison). Benefit of high-KDPI KT was greatest in patients age >50 years and patients at centers with median wait time ≥33 months. Recipients of high-KDPI KT can enjoy better long-term survival; a high-KDPI score does not automatically constitute a reason to reject a deceased donor kidney.

Association between liver transplant center performance evaluations and transplant volume

There has been increased oversight of transplant centers and stagnation in liver transplantation nationally in recent years. We hypothesized that centers that received low performance (LP) evaluations were more likely to alter protocols, resulting in reduced rates of transplants and patients placed on the waiting list. We evaluated the association of LP evaluations and transplant activity among liver transplant centers in the United States using national Scientific Registry of Transplant Recipients data (January 2007 to July 2012). We compared the average change in recipient and candidate volume and donor and patient characteristics based on whether the centers received LP evaluations. Of 92 eligible centers, 27 (29%) received at least one LP evaluation. Centers without an LP evaluation (n = 65) had an average increase of 9.3 transplants and 14.9 candidates while LP centers had an average decrease of 39.9 transplants (p < 0.01) and 67.3 candidates (p < 0.01). LP centers reduced the use of older donors, donations with longer cold ischemia, and donations after cardiac death (p-values < 0.01). There was no association between the change in transplant volume and measured performance (R(2)  = 0.002, p = 0.91). Findings indicate a strong association between performance evaluations and changes in candidate listings and transplants among liver transplant centers, with no measurable improvement in outcomes associated with reduction in transplant volume.

Big data in organ transplantation: registries and administrative claims

The field of organ transplantation benefits from large, comprehensive, transplant-specific national data sets available to researchers. In addition to the widely used Organ Procurement and Transplantation Network (OPTN)-based registries (the United Network for Organ Sharing and Scientific Registry of Transplant Recipients data sets) and United States Renal Data System (USRDS) data sets, there are other publicly available national data sets, not specific to transplantation, which have historically been underutilized in the field of transplantation. Of particular interest are the Nationwide Inpatient Sample and State Inpatient Databases, produced by the Agency for Healthcare Research and Quality. The USRDS database provides extensive data relevant to studies of kidney transplantation. Linkage of publicly available data sets to external data sources such as private claims or pharmacy data provides further resources for registry-based research. Although these resources can transcend some limitations of OPTN-based registry data, they come with their own limitations, which must be understood to avoid biased inference. This review discusses different registry-based data sources available in the United States, as well as the proper design and conduct of registry-based research.

Quantifying the risk of incompatible kidney transplantation: a multicenter study

Incompatible live donor kidney transplantation (ILDKT) offers a survival advantage over dialysis to patients with anti-HLA donor-specific antibody (DSA). Program-specific reports (PSRs) fail to account for ILDKT, placing this practice at regulatory risk. We collected DSA data, categorized as positive Luminex, negative flow crossmatch (PLNF) (n = 185), positive flow, negative cytotoxic crossmatch (PFNC) (n = 536) or positive cytotoxic crossmatch (PCC) (n = 304), from 22 centers. We tested associations between DSA, graft loss and mortality after adjusting for PSR model factors, using 9669 compatible patients as a comparison. PLNF patients had similar graft loss; however, PFNC (adjusted hazard ratio [aHR] = 1.64, 95% confidence interval [CI]: 1.15-2.23, p = 0.007) and PCC (aHR = 5.01, 95% CI: 3.71-6.77, p < 0.001) were associated with increased graft loss in the first year. PLNF patients had similar mortality; however, PFNC (aHR = 2.04; 95% CI: 1.28-3.26; p = 0.003) and PCC (aHR = 4.59; 95% CI: 2.98-7.07; p < 0.001) were associated with increased mortality. We simulated Centers for Medicare & Medicaid Services flagging to examine ILDKT's effect on the risk of being flagged. Compared to equal-quality centers performing no ILDKT, centers performing 5%, 10% or 20% PFNC had a 1.19-, 1.33- and 1.73-fold higher odds of being flagged. Centers performing 5%, 10% or 20% PCC had a 2.22-, 4.09- and 10.72-fold higher odds. Failure to account for ILDKT's increased risk places centers providing this life-saving treatment in jeopardy of regulatory intervention.

Eculizumab prevents recurrent antiphospholipid antibody syndrome and enables successful renal transplantation

Renal transplantation in patients with antiphospholipid antibodies has historically proven challenging due to increased risk for thrombosis and allograft failure. This is especially true for patients with antiphospholipid antibody syndrome (APS) and its rare subtype, the catastrophic antiphospholipid antibody syndrome (CAPS). Since a critical mechanism of thrombosis in APS/CAPS is one mediated by complement activation, we hypothesized that preemptive treatment with the terminal complement inhibitor, eculizumab, would reduce the extent of vascular injury and thrombosis, enabling renal transplantation for patients in whom it would otherwise be contraindicated. Three patients with APS, two with a history of CAPS, were treated with continuous systemic anticoagulation together with eculizumab prior to and following live donor renal transplantation. Two patients were also sensitized to human leukocyte antigens (HLA) and required plasmapheresis for reduction of donor-specific antibodies. After follow-up ranging from 4 months to 4 years, all patients have functioning renal allografts. No systemic thrombotic events or early graft losses were observed. While the appropriate duration of treatment remains to be determined, this case series suggests that complement inhibitors such as eculizumab may prove to be effective in preventing the recurrence of APS after renal transplantation.

Assessing variation in the costs of care among patients awaiting liver transplantation

Previous economic analyses of liver transplantation have focused on the cost of the transplant and subsequent care. Accurate characterization of the pretransplant costs, indexed to severity of illness, is needed to assess the economic burden of liver disease. A novel data set linking Medicare claims with transplant registry data for 15,710 liver transplant recipients was used to determine average monthly waitlist spending (N = 249,434 waitlist months) using multivariable linear regression models to adjust for recipient characteristics including Model for End-Stage Liver Disease (MELD) score. Characteristics associated with higher spending included older age, female gender, hepatocellular carcinoma, diabetes, hypertension and increasing MELD score (p < 0.05 for all). Spending increased exponentially with severity of illness: expected monthly spending at a MELD score of 30 was 10 times higher than at MELD of 20 ($22,685 vs. $2030). Monthly spending within MELD strata also varied geographically. For candidates with a MELD score of 35, spending varied from $19,548 (region 10) to $36,099 (region 7). Regional variation in waitlist costs may reflect the impact of longer waiting times on greater pretransplant hospitalization rates among high MELD score patients. Reducing the number of high MELD waitlist patients through improved medical management and novel organ allocation systems could decrease total spending for end-stage liver care.

Rates of false flagging due to statistical artifact in CMS evaluations of transplant programs: results of a stochastic simulation

The recent CMS conditions of participation are based on risk-adjusted models produced by the Scientific Registry for Transplant Recipients (SRTR). The accuracy of these models in identifying poor-performing centers is unknown. In this stochastic simulation study, 1-year mortality outcomes were simulated in virtual transplant centers, and used to flag centers according to the methods used by CMS, evaluating nine overlapping 2.5-year periods of simulated data. In a simulation where all centers had the same underlying risk, 10.2% were falsely flagged at least once during the 4.5 years of simulated evaluations. The probability of false-positive flagging was lowest in low-volume centers (2.5%) and highest in high-volume centers (16.2%). In another simulation where 5% of centers were assigned twofold risk ("poor-performing centers"), only 32% of poor-performing centers were correctly flagged. In a final simulation where each center was assigned a unique mortality risk, 94% of flagged centers had greater-than-median risk, but only 32% of flagged centers were among the 5% with highest risk. Even after disregarding known covariate limitations to the risk adjustment models, statistical noise alone leads to spurious flagging of many adequately-performing transplant centers, yet the methods used by CMS fail to flag most centers with true elevated risk.

Social media and organ donor registration: the Facebook effect

Despite countless media campaigns, organ donation rates in the United States have remained static while need has risen dramatically. New efforts to increase organ donation through public education are necessary to address the waiting list of over 100,000 patients. On May 1, 2012, the online social network, Facebook, altered its platform to allow members to specify "Organ Donor" as part of their profile. Upon such choice, members were offered a link to their state registry to complete an official designation, and their "friends" in the network were made aware of the new status as a donor. Educational links regarding donation were offered to those considering the new organ donor status. On the first day of the Facebook organ donor initiative, there were 13 054 new online registrations, representing a 21.1-fold increase over the baseline average of 616 registrations. This first-day effect ranged from 6.9× (Michigan) to 108.9× (Georgia). Registration rates remained elevated in the following 12 days. During the same time period, no increase was seen in registrations from the DMV. Novel applications of social media may prove effective in increasing organ donation rates and likewise might be utilized in other refractory public health problems in which communication and education are essential.

Optimal testing of the live organ donor for blood-borne viral pathogens: the report of a consensus conference

In 2011, live donor transmission events involving Human Immunodeficiency Virus (HIV) and Hepatitis C virus (HCV) prompted consideration of changing the process of live donor testing and evaluation in the United States. Following CDC recommendations for screening all live donors with nucleic acid testing for HIV, HCV and Hepatitis B (HBV), a consensus conference was convened to evaluate this recommendation. Workgroups focused on determining whether there was an evidence based rationale for identifying live donors at increased risk for HIV, HBV and HCV, testing options and timing for diagnosing these infections in potential donors and consent issues specific to potential increased risk donor utilization. Strategies for donor assessment were proposed. Based on review of the limited available evidence as well as guidance documents and policies currently in place in the United States and other countries, the conference participants recommended that HIV, HBV and HCV NAT should not be required for live donor evaluation; the optimal timing of live donor testing for these blood borne pathogens has not been determined.

Identifying appropriate recipients for CDC infectious risk donor kidneys

Over 10% of deceased donors in 2011 met PHS/CDC criteria for infectious risk donor (IRD), and discard rates are significantly higher for kidneys from these donors. We hypothesized that patient phenotypes exist for whom the survival benefit outweighs the infectious risk associated with IRDs. A patient-oriented Markov decision process model was developed and validated, based on SRTR data and meta-analyses of window period risks among persons with IRD behaviors. The Markov model allows patients to see, for their phenotype, their estimated survival after accepting versus declining an IRD offer, graphed over a 5-year horizon. Estimated 5-year survival differences associated with accepting IRDs ranged from -6.4% to +67.3% for a variety of patient phenotypes. Factors most predictive of the survival difference with IRD transplantation were age, PRA, previous transplant, and the expected time until the next non-IRD deceased donor offer. This study suggests that survival benefit derived from IRD kidneys varies widely by patient phenotype. Furthermore, within the inherent limitations of model-based prediction, this study demonstrates that it is possible to identify those predicted to benefit from IRD kidneys, and illustrates how estimated survival curves based on a clinical decision can be presented to better inform patient and provider decision-making.

Dynamic challenges inhibiting optimal adoption of kidney paired donation: findings of a consensus conference

While kidney paired donation (KPD) enables the utilization of living donor kidneys from healthy and willing donors incompatible with their intended recipients, the strategy poses complex challenges that have limited its adoption in United States and Canada. A consensus conference was convened March 29-30, 2012 to address the dynamic challenges and complexities of KPD that inhibit optimal implementation. Stakeholders considered donor evaluation and care, histocompatibility testing, allocation algorithms, financing, geographic challenges and implementation strategies with the goal to safely maximize KPD at every transplant center. Best practices, knowledge gaps and research goals were identified and summarized in this document.

The aggressive phenotype revisited: utilization of higher-risk liver allografts

Organ shortage has led to increased utilization of higher risk liver allografts. In kidneys, aggressive center-level use of one type of higher risk graft clustered with aggressive use of other types. In this study, we explored center-level behavior in liver utilization. We aggregated national liver transplant recipient data between 2005 and 2009 to the center-level, assigning each center an aggressiveness score based on relative utilization of higher risk livers. Aggressive centers had significantly more patients reaching high MELDs (RR 2.19, 2.33 and 2.28 for number of patients reaching MELD>20, MELD>25 and MELD>30, p<0.001), a higher organ shortage ratio (RR 1.51, 1.60 and 1.51 for number of patients reaching MELD>20, MELD>25 and MELD>30 divided by number of organs recovered at the OPO, p<0.04), and were clustered within various geographic regions, particularly regions 2, 3 and 9. Median MELD at transplant was similar between aggressive and nonaggressive centers, but average annual transplant volume was significantly higher at aggressive centers (RR 2.27, 95% CI 1.47-3.51, p<0.001). In cluster analysis, there were no obvious phenotypic patterns among centers with intermediate levels of aggressiveness. In conclusion, highwaitlist disease severity, geographic differences in organ availability, and transplant volume are the main factors associated with the aggressive utilization of higher risk livers.

Racial/ethnic differences in cancer risk after kidney transplantation

Transplant recipients have elevated cancer risk, but it is unknown if cancer risk differs across race and ethnicity as in the general population. US kidney recipients (N = 87,895) in the Transplant Cancer Match Study between 1992 and 2008 were evaluated for racial/ethnic differences in risk for six common cancers after transplantation. Compared to white recipients, black recipients had lower incidence of non-Hodgkin lymphoma (NHL) (adjusted incidence rate ratio [aIRR] 0.60, p<0.001) and higher incidence of kidney (aIRR 2.09, p<0.001) and prostate cancer (aIRR 2.14, p<0.001); Hispanic recipients had lower incidence of NHL (aIRR 0.64, p = 0.001), lung (aIRR 0.41, p < 0.001), breast (aIRR 0.53, p = 0.003) and prostate cancer (aIRR 0.72, p = 0.05). Colorectal cancer incidence was similar across groups. Standardized incidence ratios (SIRs) measured the effect of transplantation on cancer risk and were similar for most cancers (p≥0.1). However, black and Hispanic recipients had larger increases in kidney cancer risk with transplantation (SIRs: 8.96 in blacks, 5.95 in Hispanics vs. 4.44 in whites), and only blacks had elevated prostate cancer risk following transplantation (SIR: 1.21). Racial/ethnic differences in cancer risk after transplantation mirror general population patterns, except for kidney and prostate cancers where differences reflect the effects of end-stage renal disease or transplantation.

The association of center performance evaluations and kidney transplant volume in the United States

Report cards evaluating transplant center performance have received significant attention in recent years corresponding with the Centers for Medicare and Medicaid Services issue of the 2007 Conditions of Participation. Our primary aim was to evaluate the association of report card evaluations with transplant center volume. We utilized data from the Scientific Registry of Transplant Recipients (SRTR) along with six consecutive program-specific reports from January 2007 to July 2009 for adult kidney transplant centers. Among 203 centers, 46 (23%) were low performing (LP) with statistically significantly lower than expected 1-year graft or patient survival at least once during the study period. Among LP centers, there was a mean decline in transplant volume of 22.4 cases compared to a mean increase of 7.8 transplants among other centers (p = 0.001). Changes in volume between LP and other centers were significant for living, standard and expanded criteria deceased donor (ECD) transplants. LPs had a reduction in use of donors with extended cold ischemia time (p = 0.04) and private pay recipients (p = 0.03). Centers without low performance evaluations were more likely to increase the proportion of overall transplants that were ECDs relative to other centers (p = 0.04). Findings indicate a significant association between reduced kidney transplant volume and low performance report card evaluations.

Early hospital readmission after kidney transplantation: patient and center-level associations

Early hospital readmission (EHR) is associated with increased morbidity, costs and transition-of-care errors. We sought to quantify rates of and risk factors for EHR after kidney transplantation (KT). We studied 32 961 Medicare primary KT recipients (2000-2005) linked to Medicare claims through the United States Renal Data System. EHR was defined as at least one hospitalization within 30 days of initial discharge after KT. The association between EHR and recipient and transplant factors was explored using Poisson regression; hierarchical modeling was used to account for study center-level differences. The overall EHR rate was 31%, and 19 independent patient-level factors associated with EHR were identified: recipient factors included older age, African American race and various comorbidities; transplant factors included ECD, length of stay and lack of induction therapy. The unadjusted rate of EHR by center ranged from 18% to 47%, but conventional center-level factors (percent African American, percent age > 60, percent deceased donor and percent expanded criteria donor) were not associated with EHR. However, intermediate total volume and average length of stay were associated with increased EHR risk. Better identification of patients at risk for early hospital readmission following KT may guide discharge planning and early posttransplant outpatient monitoring.

Disparities in provision of transplant education by profit status of the dialysis center

Kidney transplant education is associated with higher transplantation rates; however national policies regarding optimal timing and content of transplant education are lacking. We aimed to characterize nephrologists' attitudes regarding kidney transplant education, and to compare practices between nephrologists at for-profit and nonprofit centers. We surveyed 906 nephrologist practicing in the United States. Most respondents (81%) felt the ideal time to spend on transplant education was >20 min, but only 43% reported actually doing so. Spending >20 min was associated with covering more topics, having one-on-one and repeated conversations, involving families in discussions and initiating discussions at CKD-stage 4. Providers at for-profit centers were significantly less likely to spend >20 min (RR = 0.89, 95%CI: 0.80-0.99) or involve families (RR = 0.57, 95%CI: 0.38-0.87); they reported that fewer of their patients received transplant counseling (RR = 0.58, 95%CI: 0.37-0.96), initiated transplant discussions (RR = 0.58, 95%CI: 0.38-0.88), or were eligible for transplantation (RR = 0.45, 95%CI: 0.30-0.68). Of nephrologists who spent ≤20 min, those at for-profit centers more often cited lack of reimbursement as a reason (30.0% vs. 18.9%, p = 0.02). Disparities in quality of education at for-profit centers might partially explain previously documented disparities in access to transplantation for patients at these centers. National policies detailing the optimal timing and content of transplant education are needed to improve equity.

Pre-transplant myeloid dendritic cell deficiency associated with cytomegalovirus infection and death after kidney transplantation

BACKGROUND

Dendritic cells (DCs) are potent antigen-presenting cells critical for immunity. We previously demonstrated a significant association between pre-transplant blood myeloid dendritic cell (mDC) and plasmacytoid dendritic cell (pDC) deficiency and post-transplant BK viremia in renal transplant recipients. In the current post-hoc analysis, we studied the association of these same pre-transplant DC levels with other post-transplant outcomes.

METHODS

Pre-transplant peripheral blood mDC and pDC levels were quantified using flow cytometry in 78 patients undergoing kidney transplantation. Post-transplant outcomes were analyzed, including infection, rejection, and patient death, with a median follow-up of 5.3 years. Associations between DC levels and outcomes were assessed using logistic regression analysis and Cox proportional hazards models.

RESULTS

An independent association of mDC levels with post-transplant cytomegalovirus infection (adjusted odds ratio 7.0, P = 0.01) and patient death (adjusted hazard ratio 13.0, P = 0.015) was found. No associations were demonstrated between levels of either DC subtype and bacterial infections or rejection.

CONCLUSIONS

Pre-transplant mDC deficiency is significantly associated with CMV infection and death after kidney transplantation.

Time-trends in publication productivity of young transplant surgeons in the United States

To further clarify whether the transplant surgical research workforce is adequately poised to further scientific achievement, we have investigated the publication productivity of young transplant surgeons. Our hypothesis is that recent young transplant surgeons write fewer academic manuscripts than their senior colleagues did when they were young surgeons. We compared the number of first and senior author publications in the first 5 years after completion of fellowship among recent transplant surgeons (completed fellowship 2000-2004) and former young surgeons (completed fellowship 1990-1994). Recent young surgeons wrote fewer overall manuscripts (0.94 vs. 1.67, p < 0.05), as well as basic science manuscripts (0.21 vs. 0.54, p < 0.05) and clinical manuscripts (0.73 vs. 1.14, p < 0.05). Adjusting for the number of trainees, we note that recent young surgeons published 59% fewer basic science publications (IRR 0.41, 95% CI 0.29-0.57, p < 0.001) and 33% fewer clinical publications (IRR 0.67, 95% CI 0.56-0.82, p < 0.001). Among fellows in the 2000-2004 cohort, there was a 32% lower chance of publishing at least one paper compared with fellows in the 1990-1994 cohort (IRR 0.68, 95% CI 0.51-0.89, p = 0.006). These findings raise concerns about the future place of transplant surgeons within the science that shapes our own field.

Disparities in provision of transplant information affect access to kidney transplantation

Recently Centers for Medicare and Medicaid Services (CMS) began asking providers on Form-2728 whether they informed patients about transplantation, and if not, to select a reason. The goals of this study were to describe national transplant education practices and analyze associations between practices and access to transplantation (ATT), based on United States Renal Data System (USRDS) data from 2005 to 2007. Multinomial logistic regression was used to examine factors associated with not being informed about transplantation, and modified Poisson regression to examine associations between not being informed and ATT (all models adjusted for demographics/comorbidities). Of 236,079 incident end-stage renal disease (ESRD) patients, 30.1% were not informed at time of 2728 filing, for reasons reported by providers as follows: 42.1% unassessed, 30.4% medically unfit, 16.9% unsuitable due to age, 3.1% psychologically unfit and 1.5% declined counsel. Older, obese, uninsured, Medicaid-insured and patients at for-profit centers were more likely to be unassessed. Women were more likely to be reported as unsuitable due to age, medically unfit and declined, and African Americans as psychologically unfit. Uninformed patients had a 53% lower rate of ATT, a disparity persisting in the subgroup of uninformed patients who were unassessed. Disparities in ATT may be partially explained by disparities in provision of transplant information; dialysis centers should ensure this critical intervention is offered equitably.

The aggressive phenotype: center-level patterns in the utilization of suboptimal kidneys

Despite the fact that suboptimal kidneys have worse outcomes, differences in waiting times and wait-list mortality have led to variations in the use of these kidneys. It is unknown whether aggressive center-level use of one type of suboptimal graft clusters with aggressive use of other types of suboptimal grafts, and what center characteristics are associated with an overall aggressive phenotype. United Network for Organ Sharing (UNOS) data from 2005 to 2009 for adult kidney transplant recipients was aggregated to the center level. An aggressiveness score was assigned to each center based on usage of suboptimal grafts. Deceased-donor transplant volume correlated with aggressiveness in lower volume, but not higher volume centers. Aggressive centers were mostly found in regions 2 and 9. Aggressiveness was associated with wait-list size (RR 1.69, 95% CI 1.20-2.34, p = 0.002), organ shortage (RR 2.30, 95% CI 1.57-3.37, p < 0.001) and waiting times (RR 1.75, 95% CI 1.20-2.57, p = 0.004). No centers in single-center OPOs were classified as aggressive. In cluster analysis, the most aggressive centers were aggressive in all metrics and vice versa; however, centers with intermediate aggressiveness had phenotypic patterns in their usage of suboptimal kidneys. In conclusion, wait-list size, waiting times, geographic region and OPO competition seem to be driving factors in center-level aggressiveness.

Pregnancy outcomes in kidney transplant recipients: a systematic review and meta-analysis

Approximately 50,000 women of reproductive age in the United States are currently living after kidney transplantation (KT), and another 2800 undergo KT each year. Although KT improves reproductive function in women with ESRD, studies of post-KT pregnancies are limited to a few voluntary registry analyses and numerous single-center reports. To obtain more generalizable inferences, we performed a systematic review and meta-analysis of articles published between 2000 and 2010 that reported pregnancy-related outcomes among KT recipients. Of 1343 unique studies, 50 met inclusion criteria, representing 4706 pregnancies in 3570 KT recipients. The overall post-KT live birth rate of 73.5% (95%CI 72.1-74.9) was higher than the general US population (66.7%); similarly, the overall post-KT miscarriage rate of 14.0% (95%CI 12.9-15.1) was lower (17.1%). However, complications of preeclampsia (27.0%, 95%CI 25.2-28.9), gestational diabetes (8.0%, 95%CI 6.7-9.4), Cesarean section (56.9%, 95%CI 54.9-58.9) and preterm delivery (45.6%, 95%CI 43.7-47.5) were higher than the general US population (3.8%, 3.9%, 31.9% and 12.5%, respectively). Pregnancy outcomes were more favorable in studies with lower mean maternal ages; obstetrical complications were higher in studies with shorter mean interval between KT and pregnancy. Although post-KT pregnancy is feasible, complications are relatively high and should be considered in patient counseling and clinical decision making.

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.

Young transplant surgeons and NIH funding

Transplant surgeons have historically been instrumental in advancing the science of transplantation. However, research in the current environment inevitably requires external funding, and the classic career development pathway for a junior investigator is the NIH K award. We matched transplant surgeons who completed fellowships between 1998 and 2004 with the NIH funding database, and also queried them regarding research effort and attitudes. Of 373 surgeons who completed a fellowship, only 6 (1.8%) received a K award; of these, 3 subsequently obtained R-level funding. An additional 5 individuals received an R-level grant within their first 5 years as faculty without a K award, 3 of whom had received a prior ASTS-sponsored award. Survey respondents reported extensive research experience during their training (78.8% spent median 24 months), a high proportion of graduate research degrees (36%), and a strong desire for more research time (78%). However, they reported clinical burdens and lack of mentorship as their primary perceived barriers to successful research careers. The very low rate of NIH funding for young transplant surgeons, combined with survey results that indicate their desire to participate in research, suggest institutional barriers to access that may warrant attention by the ASTS and the transplant surgery community.