Selecting DCD Recipients Using Predictive Indices.

Donation after circulatory death (DCD) allografts might represent one of the largest untapped sources of liver allografts. Our aim was to identify independent recipient risk factors that predict mortality in DCD allograft recipients to preselect optimal candidates for successful transplantation. Furthermore, we compared the application of our newly constructed DCD Recipient Selector Index (RSI) score to previously developed models to determine superiority in predicting recipient survival. Methods: Using the Organ Procurement and Transplantation Network database, we performed univariate and multivariate retrospective analyses on 4228 DCD liver allograft recipients. Results: We identified 8 significant factors and incorporated them into the weighted RSI to predict 3-mo survival following DCD liver transplantation with a C-statistic of 0.6971. The most significant recipient risk factors were recipient serum sodium levels >150 mEq/L at transplant, recipient albumin <2.0 g/dL at transplant, and a history of portal vein thrombosis. Because Model for End-Stage Liver Disease (MELD) score components were included as individual predictors, the DCD RSI predicts survival independently of MELD. Upon comparison with 3 previous recipient risk scores-Balance of Risk, Renal Risk Index, Patient-Survival Outcomes Following Liver Transplantation-the DCD RSI was determined to be superior at selecting optimal candidates pre-DCD transplantation, yielding a C-statistic of 0.6971. Conclusions: After verifying the performance of predictive indices for selection of DCD recipients, the DCD RSI is best used to preselect patients for optimized outcomes after DCD transplantation. This can increase utilization of DCD donors by improving outcomes.

Ureteral stricture after pediatric kidney transplantation: Is there a role for percutaneous antegrade ureteroplasty?

INTRODUCTION: Ureteral obstruction following pediatric kidney transplantation occurs in 5-8% of cases. We describe our experience with percutaneous antegrade ureteroplasty for the treatment of ureteral stricture in pediatric kidney transplant patients. METHODS: We retrospectively reviewed all pediatric kidney transplantation patients who presented with ureteral stricture and underwent percutaneous antegrade ureteroplasty at our institution from July 2009 to July 2021. Variables included patient demographics, timing of presentation, location and extent of stricture, ureteroplasty technique and clinical outcomes. Our primary outcome was persistent obstruction of the kidney transplant. RESULTS: Twelve patients met inclusion criteria (4.2% of all transplants). Median age at time of ureteroplasty was 11.5 years (range: 3-17.5 years). Median time from kidney transplantation to ureteroplasty was 3 months. Patency was maintained in 50% of patients. Seven patients (58.3%) required additional surgery. Four patients developed vesicoureteral reflux. Patients with persistent obstruction had a longer time from transplant to ureteroplasty compared to those who achieved patency (19.3 vs 1.3 months, p = 0.0163). Of those treated within 6 months after transplantation, two patients (25%) required surgery for persistent obstruction (p = 0.06). All patients treated >1 year after transplantation had persistent obstruction following ureteroplasty (p = 0.06). CONCLUSION: Percutaneous antegrade ureteroplasty can be considered a viable minimally invasive treatment option for pediatric patients who develop early ureteral obstruction (<6 months) following kidney transplantation. In patients who are successfully treated with ureteroplasty, 67% can develop vesicoureteral reflux into the transplant kidney. Patients who fail early percutaneous ureteroplasty or develop obstruction >1 year after transplantation are best managed with surgical intervention.

Systematic review: hepatitis C viraemic allografts to hepatitis C-negative recipients in solid organ transplantation.

BACKGROUND: Given the success of direct-acting antivirals (DAAs) in treating hepatitis C (HCV), interest is growing in utilizing solid organs from allografts with active HCV to expand donor availability. AIM: To review post-transplant outcomes and patient survival in HCV-negative recipients receiving solid organ transplants (SOT) from viraemic, that is, HCV+/NAT+ (nucleic acid testing) allografts. METHODS: A literature search was conducted on PubMed and EMBASE from 01/01/2007 to 4/17/2021 for articles matching eligibility criteria. Two authors independently screened titles and abstracts. Disagreements were solved by a third independent reviewer. Methodological quality assessment was done using a modified Newcastle-Ottawa scale (NOS). Data synthesis was done qualitatively using median, ranges and percentages. RESULTS: Thirty-five studies were included (or 852 SOTs): 343 kidney, 233 heart, 204 liver, and 72 lung transplants from viraemic allografts. Of the recipients eligible for sustained virological response at 12 weeks (SVR12) calculation, 100% achieved cure from HCV. No deaths/graft failures were reported to be related to HCV transmission. Seven SOT recipients had viral relapse, with all seven patients treated successfully. Four patients developed fibrosing cholestatic hepatitis with complete resolution post-treatment. CONCLUSIONS: Transplanting viraemic organs into uninfected individuals can become the standard of care for patients who do not have contraindications to DAAs.

Prediction of Kidney Allograft Discard Before Procurement: The Kidney Discard Risk Index.

OBJECTIVES: There is an 18.9% discard rate among kidney allografts. Here, we aimed to determine predictors of kidney discard and construct an index to identify high-probability discard kidney allografts prior to procurement. MATERIALS AND METHODS: A total of 102 246 potential kidney allograft donors from the Organ Procurement and Transplantation Network database were used in this analysis. The cohort was randomized into 2 groups. The training set included 67% of the cohort and was used to derive a predictive index for discard that comprised 21 factors identified by univariate and multivariate logistic regression analysis. The validation set included 33% and was used to internally validate the kidney discard risk index. RESULTS: In 77.3% of donors, at least 1 kidney was used for transplant, whereas in 22.7% of donors, both kidneys were discarded. The kidney discard risk index was highly predictive of discard with a C statistic of 0.89 (0.88-0.89). The bottom 10th percentile had a discard rate of 0.73%, whereas the top 10th percentile had a discard rate of 83.65%. The 3 most predictive factors for discard were age, creatinine level, and hepatitis C antibody status. CONCLUSIONS: We identified 21 factors predictive of discard prior to donor procurement and used these to develop a kidney discard risk index with a C statistic of 0.89.

Splenic Artery Transposition for Liver Transplantation: An Underutilized Technique?

BACKGROUND: Successful liver transplantation is dependent on restoration of hepatic arterial (HA) flow. Although uncommon, some native recipient HAs are not suitable or inadequate for anastomosis, thereby necessitating extra-anatomic HA reconstruction. Splenic artery transposition (SAT) is 1 method of HA reconstruction, in which the recipient splenic artery is transposed to reestablish perfusion of the donor liver. Due to the rarity of the technique, literature describing outcomes is limited. In the current report, we describe 3 patients (2 adults, 1 pediatric) who underwent complex upper abdominal surgery before whole-organ deceased donor liver transplantation with SAT. METHODS: The demographic and patient care information was collected prospectively and subsequently reviewed retrospectively. Given the de-identified nature of the data included, this study was exempt from approval from an ethics board. RESULTS: Recipient splenic arteries were dissected from their origin at the celiac trunk, for approximately 3-5 cm to ensure a gentle anterior-cranial curve toward the right upper quadrant, allowing anastomosis to the donor celiac trunk in an end-to-end fashion. Postoperatively, all 3 patients had rapid normalization of liver function tests and brisk HA flow demonstrated by Doppler ultrasound. Longer-term follow-up, ranging from 1 to 3 years, reveals continued patency of the reconstructed HAs and liver function tests within normal limits. CONCLUSIONS: Our experience points to SAT as a safe and effective technique for extra-anatomic HA reconstruction.

Liver transplant in a recently COVID-19 positive child with hepatoblastoma.

We describe the successful pediatric liver transplant for unresectable hepatoblastoma in a 4-year-old male with COVID-19 prior to transplant. The first negative NP swab was documented 1 month after initial diagnosis, when SARS-CoV-2 antibodies were also detected. The patient was actively listed for liver transplant after completing four blocks of a SIOPEL-4 based regimen due to his PRETEXT IV disease which remained unresectable. Following three additional negative NP swabs and resolution of symptoms for 4 weeks, he underwent a whole-organ pediatric liver transplant. COVID-19 positivity determined via NP swab SARS-CoV-2 real-time RT-PCR (Hologic Aptima SARS-CoV-2 RT-PCR assay). IgG and IgM total SARS- CoV-2 antibodies detected by Ortho Clinical Diagnostics VITROS® Immunodiagnostics Products Anti-SARS-CoV-2 Test. Patient received standard prednisone and tacrolimus-based immunosuppression without induction therapy following transplant. Post-transplant course was remarkable for neutropenia and thrombocytopenia, with discharge home on post-transplant day #11. Surveillance tests have remained negative with persistent SARS-CoV-2 IgG antibodies at 6 weeks after transplant. We describe one of the earliest, if not the first case of liver transplant following recent recovery from COVID-19 in a pediatric patient with a lethal malignant liver tumor. A better understanding of how to balance the risk profile of transplant in the setting of COVID-19 with disease progression if transplant is not performed is needed. We followed existing ASTS guidelines to document clearance of the viral infection and resolution of symptoms before transplant. This case highlights that pediatric liver transplantation can be safely performed upon clearance of COVID-19.

The pediatric solid organ transplant experience with COVID-19: An initial multi-center, multi-organ case series.

The clinical course of COVID-19 in pediatric solid organ transplant recipients remains ambiguous. Though preliminary experiences with adult transplant recipients have been published, literature centered on the pediatric population is limited. We herein report a multi-center, multi-organ cohort analysis of COVID-19-positive transplant recipients ≤ 18 years at time of transplant. Data were collected via institutions' respective electronic medical record systems. Local review boards approved this cross-institutional study. Among 5 transplant centers, 26 patients (62% male) were reviewed with a median age of 8 years. Six were heart recipients, 8 kidney, 10 liver, and 2 lung. Presenting symptoms included cough (n = 12 (46%)), fever (n = 9 (35%)), dry/sore throat (n = 3 (12%)), rhinorrhea (n = 3 (12%)), anosmia (n = 2 (8%)), chest pain (n = 2 (8%)), diarrhea (n = 2 (8%)), dyspnea (n = 1 (4%)), and headache (n = 1 (4%)). Six patients (23%) were asymptomatic. No patient required supplemental oxygen, intubation, or ECMO. Eight patients (31%) were hospitalized at time of diagnosis, 3 of whom were already admitted for unrelated problems. Post-transplant immunosuppression was reduced for only 2 patients (8%). All symptomatic patients recovered within 7 days. Our multi-institutional experience suggests the prognoses of pediatric transplant recipients infected with COVID-19 may mirror those of immunocompetent children, with infrequent hospitalization and minimal treatment, if any, required.

A learning curve in using orphan liver allografts for transplantation.

Given the critical shortage of donor livers, marginal liver allografts have potential to increase donor supply. We investigate trends and long-term outcomes of liver transplant using national share allografts transplanted after rejection at the local and regional levels. We studied a cohort of 75 050 candidates listed in the Organ Procurement and Transplantation Network for liver transplantation between 2002 and 2016. We compared patients receiving national share and regional/local share allografts from 2002-2006, 2007-2011, and 2012-2016, performing multivariate Cox regression for graft survival. Recipient and center-level covariates that were not significant (P < .05) were removed. Graft survival of national share allografts improved over time. National share allografts had a 26% increased risk for graft failure in 2002-2006 but no impact on graft survival in 2007-2011 and 2012-2016. The cold ischemia time (CIT) of national share allografts decreased from 10.4 to 8.0 hours. We demonstrate that CIT had significant impact on graft survival using national share allografts (CIT <6 hours: hazard ratio 0.75 and CIT >12 hours: hazard ratio 1.25). Despite a trend toward sicker recipients and poorer quality allografts, graft survival outcomes using national share allografts have improved to benchmark levels. Reduction in cold ischemia time is a possible explanation.

The decreasing predictive power of MELD in an era of changing etiology of liver disease.

The field of liver transplantation has shifted considerably in the MELD era, including changing allocation, immunosuppression, and liver failure etiologies, as well as better supportive therapies. Our aim was to evaluate the predictive accuracy of the MELD score over time. The United Network for Organ Sharing provided de-identified data on 120 156 patients listed for liver transplant from 2002-2016. The ability of the MELD score to predict 90-day mortality was evaluated by a concordance (C-) statistic and corroborated with competing risk analysis. The MELD score's concordance with 90-day mortality has downtrended from 0.80 in 2003 to 0.70 in 2015. While lab MELD scores at listing and transplant climbed in that interval, score at waitlist death remained steady near 35. Listing age increased from 50 to 54 years. HCV-positive status at listing dropped from 33 to 17%. The concordance of MELD and mortality does not differ with age (>60 = 0.73, <60 = 0.74), but is lower in diseases that are increasing most rapidly-alcoholic liver disease and non-alcoholic fatty liver disease-and higher in those that are declining, particularly in HCV-positive patients (HCV positive = 0.77; negative = 0.73). While MELD still predicts mortality, its accuracy has decreased; changing etiology of disease may contribute.

Successful kidney transplantation in a small child with end-stage renal disease due to angiotensin receptor blocker fetopathy and atretic inferior vena cava.

Kidney transplantation is the treatment of choice in pediatric patients with end-stage renal disease. This population presents technical challenges particularly in those less than 20 kg due to anomalous anatomy, vascular access issues prior to transplantation, and a generally small size for age. Standard allograft outflow is usually achieved utilizing the iliac veins or IVC. When use of the iliocaval system is not feasible, alternative anastomosis must be considered. Herein, we report a case of a pediatric kidney transplantation where successful allograft outflow was achieved using the SMV when he was found to have an atretic IVC intraoperatively. In this setting, use of the portal system was required to achieve adequate allograft outflow. We created a donor iliac graft for added length to anastomose the renal vein with the SMV. In the setting of IVC occlusion with poor drainage, we utilized a patent vessel with larger caliber for outflow to reduce the risk of high venous pressures, allograft failure, venous rotation, and thrombosis. We conclude that the SMV may serve as an alternative outflow tract in the small pediatric patient and provides the vessel caliber needed to reduce the risks of complications.

Intraoperative blood loss and transfusion during primary pediatric liver transplantation: A single-center experience.

Children undergoing liver transplantation are at a significant risk for intraoperative hemorrhage and thrombotic complications, we aim to identify novel risk factors for massive intraoperative blood loss and transfusion in PLT recipients and describe its impact on graft survival and hospital LOS. We reviewed all primary PLTs performed at our institution between September 2007 and September 2016. Data are presented as n (%) or median (interquartile range). EBL was standardized by weight. Massive EBL and MT were defined as greater than the 85th percentile of the cohort. 250 transplantations were performed during the study period. 38 (15%) recipients had massive EBL, and LOS was 31.5 (15-58) days compared to 11 (7-21) days among those without massive EBL (P < 0.001). MT median LOS was 34 (14-59) days compared to 11 (7-21) days among those without MT (P = 0.001). Upon backward stepwise regression, technical variant graft, operative time, and transfusion of FFP, platelet, and/or cryoprecipitate were significant independent risk factors for massive EBL and MT, while admission from home was a protective factor. Recipient weight was a significant independent risk factor for MT alone. Massive EBL and MT were not statistically significant for overall graft survival. MT was, however, a significant risk factor for 30-day graft loss. PLT recipients with massive EBL or MT had significantly longer LOS and increased 30-day graft loss in patients who required MT. We identified longer operative time and technical variant graft were significant independent risk factors for massive EBL and MT, while being admitted from home was a protective factor.

No Gains in Long-term Survival After Liver Transplantation Over the Past Three Decades.

OBJECTIVE: The aim of this study was to assess improvements in long-term survival after liver transplant by analyzing outcomes in transplant recipients who survived beyond 1 year. SUMMARY OF BACKGROUND DATA: Gains in short-term survival following liver transplantation have been gratifying. One-year survival in 1986 was 66% improved to over 92% in 2015. However, little is known about why long-term has not seen similar success. METHODS: We analyzed 111,568 recipients from 1987 to 2016 using the Kaplan-Meier method for time-to-event analysis and multivariable Cox regression. RESULTS: There were no significant gains in unadjusted long-term outcomes among 1-year survivors over the past 30 years. Only the time periods of 1987 to 1990 [hazard ratio (HR) 1.35, confidence interval CI) 1.28-1.42] and 1991 to 1995 (HR 1.17, CI 1.13-1.21) had a minor increase in risk compared with the period 2011 to 2016. Cause of death analysis suggests malignancy after transplantation is a growing problem and preventing recurrent hepatitis C with direct-acting antivirals (DDAs) may only have a limited impact. Furthermore, rejection leading to graft failure and death had a rare occurrence (1.7% of long-term deaths) especially when compared with the sequelae of long-term immunosuppression: malignancy (16.4%), nonrejection graft failure (9.8%), and infection (10.5%) (P < 0.001). CONCLUSION: In stark contrast to short-term survival, there have been no appreciable improvements in long-term survival following liver transplantation among 1-year survivors. Long-term sequelae of immunosuppression, including malignancy and infection, are the most common causes of death. This study highlights the need for better long-term immunosuppression management.

Impact of the Treating Hospital on Care Outcomes for Hepatocellular Carcinoma.

Multidisciplinary hepatocellular carcinoma (HCC) treatment is associated with optimal outcomes. There are few data analyzing the impact of treating hospitals' therapeutic offerings on survival. We performed a retrospective cohort study of patients aged 18-70 years with HCC in the National Cancer Database (2004-2012). Hospitals were categorized based on the level of treatment offered (Type I-nonsurgical; Type II-ablation; Type III-resection; Type IV-transplant). Associations between overall risk of death and hospital type were evaluated with multivariable Cox shared frailty modeling. Among 50,381 patients, 65% received care in Type IV hospitals, 26% in Type III, 3% in Type II, and 6% in Type I. Overall 5-year survival across modalities was highest at Type IV hospitals (untreated: Type IV-13.1% versus Type I-5.7%, Type II-7.0%, Type III-7.4% [log-rank, P < 0.001]; chemotherapy and/or radiation: Type IV-18.1% versus Type I-3.6%, Type II-4.6%, Type III-7.7% [log-rank, P < 0.001]; ablation: Type IV-33.3% versus Type II-13.6%, Type III-23.6% [log-rank, P < 0.001]; resection: Type IV-48.4% versus Type III-39.1% [log-rank, P < 0.001]). Risk of death demonstrated a dose-response relationship with the hospital type-Type I (ref); Type II (hazard ratio [HR] 0.81, 95% confidence interval [0.73-0.90]); Type III (HR 0.67 [0.62-0.72]); Type IV hospitals (HR 0.43 [0.39-0.47]). Conclusion: Although care at hospitals offering the full complement of HCC treatments is associated with decreased risk of death, one third of patients are not treated at these hospitals. These data can inform the value of health policy initiatives regarding regionalization of HCC care.

Mineral and Bone Disorders After Kidney Transplantation.

The risk of mineral and bone disorders among patients with chronic kidney disease is substantially elevated, owing largely to alterations in calcium, phosphorus, vitamin D, parathyroid hormone, and fibroblast growth factor 23. The interwoven relationship among these minerals and hormones results in maladaptive responses that are differentially affected by the process of kidney transplantation. Interpretation of conventional labs, imaging, and other fracture risk assessment tools are not standardized in the post-transplant setting. Post-transplant bone disease is not uniformly improved and considerable variation exists in monitoring and treatment practices. A spectrum of abnormalities such as hypophosphatemia, hypercalcemia, hyperparathyroidism, osteomalacia, osteopenia, and osteoporosis are commonly encountered in the post-transplant period. Thus, reducing fracture risk and other bone-related complications requires recognition of these abnormalities along with the risk incurred by concomitant immunosuppression use. As kidney transplant recipients continue to age, the drivers of bone disease vary throughout the post-transplant period among persistent hyperparathyroidism, de novo hyperparathyroidism, and osteoporosis. The use of anti-resorptive therapies require understanding of different options and the clinical scenarios that warrant their use. With limited studies underscoring clinical events such as fractures, expert understanding of MBD physiology, and surrogate marker interpretation is needed to determine ideal and individualized therapy.

Reoperative complications following pediatric liver transplantation.

BACKGROUND: The aim of this study is to describe the incidence and impact of reoperation following pediatric liver transplantation, as well as the indications and risk factors for these complications. METHODS: All primary pediatric liver transplants performed at our institution between January 2012 and September 2016 were reviewed. A reoperative complication was defined as a complication requiring return to the operating room within 30 days or the same hospital admission as the transplant operation, excluding retransplantation. RESULTS: Among the 144 pediatric liver transplants performed during the study period, 9% of the recipients required reoperation. The most common indications for reoperation were bleeding and bowel complications. There was no significant difference in the graft survival of patients with a reoperation and those without a reoperation (p = 0.780), but patients with a reoperation had a significantly longer hospital length of stay (median of 39 days vs. 11 days, p = 0.001). Variant donor arterial anatomy, transplant operative time, intraoperative blood loss, transfusion volume of packed red blood cells or cell saver per weight, and transfusion with fresh frozen plasma, platelets, or cryoprecipitate were significantly associated with reoperation upon univariable logistic regression, but none of these risk factors remained statistically significant upon multivariable regression. CONCLUSION: At our institution, reoperation did not significantly impact graft survival. We identified variant donor arterial anatomy, transplant operative time, intraoperative blood loss, transfusion volume of packed red blood cells or cell saver per weight, and transfusion with fresh frozen plasma, platelets, or cryoprecipitate as risk factors for reoperation, although none of these risk factors demonstrated independent association with reoperation in a multivariable model. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: Level III.