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BACKGOUND B cells contribute to chronic transplant rejection by producing donor-specific antibodies and promoting T cell response , but how these processes are regulated at the transcriptional level remains unclear. Herein, we investigate the role of transcription factor interferon regulatory factor 4 (IRF4) in controlling B cell response during chronic transplant rejection. METHODS We generated the Irf4gfp reporter mice to determine IRF4 expression in B cell lineage . We then used mice with B cell-specific IRF4 deletion to define the role of IRF4 in B cell response after NP-KLH immunization or allogeneic heart transplantation . In particular, graft survival and histology, as well as B and T cell responses, were evaluated after transplantation. RESULTS IRF4 is dynamically expressed at different stages of B cell development and is absent in germinal center (GC) B cells. However, IRF4 ablation in the B cell lineage primarily eliminates GC B cells in both naive and NP-KLH immunized mice. In the transplantation setting, IRF4 functions intrinsically in B cells and governs allogeneic B cell responses at multiple levels, including GC B cell generation, plasma cell differentiation, donor-specific antibody production , and support of T cell response. B cell-specific IRF4 deletion combined with transient CTLA4-Ig treatment abrogates acute and chronic cardiac allograft rejection in naive recipient mice but not in donor skin-sensitized recipients. CONCLUSIONS B cells require IRF4 to mediate chronic transplant rejection. IRF4 ablation in B cells abrogates allogeneic B cell responses and may also inhibit the ability of B cells to prime allogenic T cells . Targeting IRF4 in B cells represents a potential therapeutic strategy for eliminating chronic transplant rejection.

Progress in deceased donor intervention research has been limited. Development of an in silico model of deceased donor physiology may elucidate potential therapeutic targets and provide an efficient mechanism for testing proposed deceased donor interventions. In this study, we report a preliminary in silico model of deceased kidney donor injury built, calibrated, and validated based on data from published animal and human studies. We demonstrate that the in silico model behaves like animal studies of brain death pathophysiology with respect to upstream markers of renal injury including hemodynamics, oxygenation, cytokines expression, and inflammation. Therapeutic hypothermia, a deceased donor intervention studied in human trials, is performed to demonstrate the model's ability to mimic an established clinical trial. Finally, future directions for developing this concept into a functional, clinically applicable model are discussed.

Background Combined liver-kidney transplantation (CLKT) improves survival for liver transplant recipients with renal dysfunction; however, the tenuous perioperative hemodynamic and metabolic milieu in high-acuity CLKT recipients increases delayed graft function and kidney allograft failure. We sought to analyze whether delayed KT through pumping would improve kidney outcomes following CLKT. Methods A retrospective analysis (University of California Los Angeles [n = 145], Houston Methodist Hospital [n = 79]) was performed in all adults receiving CLKT at 2 high-volume transplant centers from February 2004 to January 2017, and recipients were analyzed for patient and allograft survival as well as renal outcomes following CLKT. Results A total of 63 patients (28.1%) underwent delayed implantation of pumped kidneys during CLKT (dCLKT) and 161 patients (71.9%) received early implantation of nonpumped kidneys during CLKT (eCLKT). Most recipients were high-acuity with median biologic model of end-stage liver disease (MELD) score of, 35 for dCLKT and 34 for eCLKT (P = ns). Pretransplant, dCLKT had longer intensive care unit stay, were more often intubated, and had greater vasopressor use. Despite this, dCLKT exhibited improved 1-, 3-, and 5-year patient and kidney survival (P = 0.02) and decreased length of stay (P = 0.001), kidney allograft failure (P = 0.012), and dialysis duration (P = 0.031). This reduced kidney allograft futility (death or continued need for hemodialysis within 3 mo posttransplant) for dCLKT (6.3%) compared with eCLKT (19.9%) (P = 0.013). Conclusions Delayed implantation of pumped kidneys is associated with improved patient and renal allograft survival and decreased hospital length of stay despite longer kidney cold ischemia. These data should inform the ethical debate as to the futility of performing CLKT in high-acuity recipients.

Response to two doses of a nucleoside-modified messenger ribonucleic acid (mRNA) vaccine was evaluated in a large solid-organ transplant program. mRNA COVID-19 vaccine was administered to transplant candidates and recipients who met study inclusion criteria. Qualitative anti-SARS-CoV-2 Spike Total Immunoglobulin (Ig) and IgG-specific assays, and a semi-quantitative test for anti-SARS-CoV-2 Spike protein IgG were measured in 241 (17.2%) transplant candidates and 1163 (82.8%) transplant recipients; 55.2% of whom were non-Hispanic White and 44.8% identified as another race. Transplant recipients were a median (IQR) of 3.2 (1.1, 6.8) years from transplantation. Response differed by transplant status: 96.0% versus 43.2% by the anti-SARS-CoV-2 Total Ig (candidates vs. recipients, respectively), 93.5% versus 11.6% by the anti-SARS-CoV-2 IgG assay, and 91.9% versus 30.1% by anti-spike titers after two doses of vaccine. Multivariable analysis revealed candidates had higher likelihood of response versus recipients (odds ratio [OR], 14.6; 95 %CI 2.19, 98.11; P = .02). A slightly lower response was demonstrated in older patients (OR .96; 95 %CI .94, .99; P = .002), patients taking antimetabolites (OR, .21; 95% CI .08, .51; P = .001). Vaccination prior to transplantation should be encouraged.

Background. Orthostatic hypotension (OH) is a poorly understood complication of simultaneous pancreas–kidney (SPK) transplantation. We sought to determine the incidence, timing, and relationship of OH to rapid glycemic control in the early posttransplant period. Methods. This was a nonrandomized retrospective single-center review of 75 SPK and 19 kidney-alone (KA) recipients with type 1 diabetes (DM). Results. OH occurred in 57 (76%) SPK versus 2 (10%) KA recipients (odds ratio [OR] 61.72, 95% confidence interval [CI], 9.69-393.01; P < 0.001). The median onset of OH was 12 (interquartile range [IQR] 9–18) days posttransplant and resolved in 85% of SPK recipients after a median of 2.5 (IQR 1.2–6.3) months. Among SPK recipients, independent risk factors for OH were a shorter duration of DM (OR 0.85, 95% CI, 0.73-0.98; P = 0.03) and rapid glycemic control in the early posttransplant period (OR 1.13, 95% CI, 1.01-1.27; P = 0.04), as evidenced by a larger percent change in hemoglobin A1c (HbA1c) from transplant to month 3. OH patients had a higher median baseline HbA1c [8.3% (IQR 7.2–10.0) versus 7.1% (IQR 6.8–8.3); P = 0.07], lower median 3-month HbA1c [4.8% (IQR 4.6–5.2) versus 5.2% (IQR 5.0–5.4); P = 0.02], and a larger reduction in HbA1c over time as compared to recipients without OH (P < 0.01). Conclusions. Our results show that OH is more likely to occur following SPK versus KA transplantation and is strongly associated with rapid glucose normalization within the early posttransplant period.

Severe obesity can increase risk of complications after kidney transplantation. There is a paucity of literature on bariatric surgery outcomes in renal transplant candidates. The objective of this study was to analyze outcomes of bariatric surgery as a weight reduction strategy for patients with kidney failure to enhance eligibility for kidney transplantation. We performed a retrospective analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database at a single institution for patients with chronic kidney disease receiving hemodialysis therapy (CKD G5D) undergoing bariatric surgery between 2011 and 2018. Of 2363 patients who underwent bariatric surgery, 38 (1.6%) had CKD G5D; median age (range) was 49 years (33; 69), 52.6% were female, and mean BMI was 44.2 kg/m2. Twenty-four patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB), and 14 patients underwent laparoscopic sleeve gastrectomy. Seventeen patients (46%, n=37) had a BMI≤35 at 6 months, while 25 patients (75.8%, n=33) achieved a BMI≤35 at 12 months. Of these, 18 patients (47%) were listed for kidney transplant, and 8 patients (21%) received kidney transplant. There was no statistically significant difference between sleeve and LRYGB procedures in patients who reached BMI of 35 at 12 months (P=0.58). Median length of stay was 2.3 days. Thirty-day readmission rate was 2 patients (5.3%), and 2 patients (5.3%) required reoperation (one for bleeding, one for acute recurrent hiatal hernia). No mortality occurred. Laparoscopic bariatric surgery offers effective weight loss for CKD G5D patients to achieve transplant eligibility with acceptable outcomes.

BACKGROUND Careful donor-recipient matching and reduced ischemia times have improved outcomes following donation after circulatory death (DCD) liver transplantation (LT). This study examines a single-center experience with DCD LT including high-acuity and hospitalized recipients. METHODS DCD LT outcomes were compared to a propensity score-matched (PSM) donation after brain death (DBD) LT cohort (1:4); 32 DCD LT patients and 128 PSM DBD LT patients transplanted from 2008 to 2018 were included. Analyses included Kaplan-Meier estimates and Cox proportional hazards models examining patient and graft survival. RESULTS Median MELD score in the DCD LT cohort was 22, with median MELD of 27 for DCD LT recipients with decompensated cirrhosis. No difference in mortality or graft loss was found (p

The novel coronavirus SARS-CoV-2 [coronavirus disease 2019 (COVID-19)] is a highly contagious and devastating virus that has currently infected over 2.5 million people worldwide and resulted in 177 641 deaths as of April 2020.1 Although most people diagnosed with COVID-19 exhibit mild-to-moderate symptoms, early reports from China described vulnerable patient populations, such as the elderly and those with chronic underlying medical conditions including the immunosuppressed, having more severe COVID-19-related illness compared to the general population.2,3 Solid organ transplant (SOT) recipients are one of the largest cohorts of immunosuppressed patients, yet little is known about their risk of contracting the virus, postinfection outcomes, and effect of immunosuppression on the clinical course of the disease. Unique challenges, such as immunosuppression management and interpretation of laboratory data, also exist. Current treatment strategies borrow upon prior experience from other pandemics, such as severe acute respiratory syndrome (SARS) and influenza A virus subtype.4 SARS-CoV-2 primarily affects the respiratory tract, progressing from pneumonia to acute respiratory distress syndrome in severe cases.5 In these cases, there is a recognized cytokine release syndrome (CRS) that when occurs results in multiorgan dysfunction and failure.6 The role of immunosuppression in mounting such inflammatory response is unclear. Inflammatory markers, such as C-reactive protein (CRP), lactate dehydrogenase (LDH), and D-dimer, may reflect disease progression and/or severity.7 Lymphopenia is reported as a common presentation among COVID-19 positive patients.8,9 Treatment options are limited. Antivirals such as hydroxychloroquine (HCQ) with or without azithromycin are widely used empiric options. Remdesivir, an RNA polymerase inhibitor, has shown in vitro activity against SARS-CoV-2 and is currently under phase 3 trial.10 Investigational agents to combat the cytokine response, such as tocilizumab, an interleukin 6 (IL-6) receptor inhibitor, are being studied. Although the exact role of immunosuppression on the progression of COVID-19 is unknown, early case reports of kidney transplant recipients suggest minimizing immunosuppression while continuing steroidal therapy.11 Evaluation of clinical symptoms, utility of biomarkers, and progression of disease are important to understand for optimizing the management in COVID-19 positive SOT recipients. The effect of COVID-19 on the heart, lung, liver, pancreas, and kidney transplant organ systems is not well described. Herein, we present our experience with 21 consecutive SOT recipients diagnosed with COVID-19 at the Houston Methodist J.C. Walter Transplant Center followed to April 22, 2020.

Combined thoracic organ and liver transplantation has been shown to be a viable treatment option for patients with end-stage disease lung or heart and disease. There are increasing number of cases reported in the literature, as the number of institutions utilizing this strategy is growing. Herein, we review the current literature of combined thoracic and liver transplantation.A larger number of combined heart or lung and liver transplants (CHLT and CLLT) are being performed. A recent literature search showed approximately 231 CHLT and 89 CLLT and being described. One-year patient survival ranged from 71 to 80% for CLLT and 80-93% for CHLT, respectively. Indications for combined transplant and disease-specific outcomes are still being evaluated. Additionally, salvage modalities such as extracorporeal membrane oxygenation and ex-vivo lung perfusion are also being described.Combined thoracic and liver transplant continues to be a viable treatment option for patients with end-stage disease that would likely not survive single transplant alone. Salvage modalities, such as extracorporeal membrane oxygenation and ex-vivo lung perfusion, may help in extending candidacy for this combined transplant. Outcomes, to date, are similar to results observed for solitary thoracic organ recipients, justifying CHLT and CLLT as a viable option for these patients. Continued identification of outcomes is needed to justify allocation of dual organs to a single recipient.

Background. Data about vaccine efficacy in solid organ transplant patients are limited. We previously reported our initial observation of a 6.2% immunogenicity rate in kidney transplant recipients (KTRs) after administration of 1 dose of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine. We sought to report our observations of anti-SARS-CoV-2 antibody in KTRs after 2 doses of the SARS-CoV-2 mRNA vaccine. Methods. We identified 105 KTRs who received 2 doses of the Pfizer-BioNTech or Moderna mRNA-1273 vaccine per availability and had anti-SARS-CoV-2 labs obtained at least 2 wk following administration of the second dose. Antibody testing was performed using 3 clinically validated qualitative and semiquantitative assays. Results. KTRs had a 36.2% antibody response rate, whereas an age ≥68 years and a longer time from transplant were factors associated with antibody response. Conclusions. The low antibody response in KTRs may be associated with the immunosuppressive state. More data are needed to evaluate if KTRs may require higher vaccine doses or an additional booster dose to increase their ability to mount an immune response to the SARS-CoV-2 vaccine.

PURPOSE OF REVIEW BK virus is a significant risk factor for kidney allograft dysfunction and loss among renal transplant recipients. Currently, there is no proven effective treatment except for the reduction of immunosuppression. In this review, we discuss diagnostic challenges and current treatment options for BK in kidney transplant recipients. RECENT FINDINGS Antiviral and antibiotic therapies have been employed for BK viraemia with variable efficacy. In addition, novel therapeutic regimens such as adoptive transfer of targeted T cells have been described as possible treatment options for recipients with BK nephropathy. BK can also be seen in the native kidneys of pancreas, heart, lung and liver transplant recipients, suggesting that BK screening measures should be employed to other solid organ transplant recipients. SUMMARY Early screening for BK combined with reduction of immunosuppression remains the mainstay of treatment for BK viraemia. New therapeutic advances demonstrate promise in vitro; however, the in-vivo efficacy will be demonstrated by future studies.

BACKGROUND: There is debate whether simultaneous lung-liver transplant (LLT) long-term outcomes warrant allocation of 2 organs to a single recipient. We hypothesized that LLT recipients would have improved posttransplant survival compared to matched single-organ lung recipients with an equivalent degree of liver dysfunction. METHODS: The OPTN/UNOS STAR file was queried for adult candidates for LLT and isolated lung transplantation from 2006–2016. Waitlist mortality and transplant odds were calculated for all candidates. Donor and recipient demographic characteristics were compiled and compared. LLT recipients were matched 1:2 with a nearest neighbor method to single-organ lung recipients. Kaplan-Meier methods with log-rank test compared long-term survival between groups. Univariate regression was used to calculate the association of LLT and mortality within 6-months of transplant. A proportional hazards model was used to calculate risk-adjusted mortality after 6-months posttransplantation. RESULTS: Thirty-eight LLT patients were matched to 75 single-organ lung recipients. After matching, no differences in baseline demographics or liver function were observed between cohorts. Length of stay was significantly longer in LLT recipients compared to isolated lung recipients (45.89 days vs. 22.44 days, p

BACKGROUND: The effect of adrenal replacement therapy (ART) with hydrocortisone on critical endpoints such as infection and mortality in critically ill patients with cirrhosis remains unclear. We evaluated our indications for ART in patients with cirrhosis with clinical symptoms of adrenal insufficiency (AI), and examined the rate of peri-transplant fungal colonization and mortality associated with ART. METHODS: Seventy-eight patients with cirrhosis admitted to our institution's surgical intensive care unit (ICU) over a 4-year period met criteria for AI by vasopressor requirement and baseline cortisol levels. Outcomes included disposition at 90-days, fungal colonization, and fungal infection in the presence or absence of ART. RESULTS: In total, 56 patients received hydrocortisone (HC+) while 22 did not (HC-). The HC+ and HC- groups had comparable median Model for End-stage Liver Disease (MELD) scores (26.5 vs. 25, respectively; p=0.93), median ICU lengths of stay (23 vs. 20 days, respectively; p=0.54) and median cortisol levels (18 μg/dL for both, p=0.87). Fungal cultures (FC) from blood, urine or bronchoalveolar lavage/sputum were positive for 44% of HC+, and 40.9% of HC- (p=0.77) had mortality rates between HC+ and HC- groups that were not significantly different (60.7% vs. 50%, respectively; p=0.39; α=0.05). The 90-day outcomes for HC+ vs. HC- (39.3% vs. 50% discharged, respectively; p=0.39; α=0.05) and those surviving to transplant (17.9% vs. 36.4%, respectively; p=0.08; α=0.05) were not significantly different between the two groups. CONCLUSION: In this small single-center series, we found that steroid administration for AI does not affect the rate of fungal colonization/infection or mortality. Further prospective studies are required to determine the utility of ART and factors affecting the rate of FC and mortality in these patients.

Renal transplantation remains the definitive treatment for end-stage renal disease (ESRD). The shorter renal vein in right donor nephrectomies is associated with higher incidence of technical failure. We present here our experience with autologous internal jugular vein (IJV) conduits to facilitate living-donor transplants. Six patients underwent right, living-donor kidney transplant with simultaneous IJV harvest over a 1-year period. All had bilateral jugular duplex scans preoperatively and were placed on aspirin 81 mg postoperatively. Patient demographics, comorbidities, and laboratories were retrospectively queried. Postoperative follow-up and examination were performed per institutional protocol. The mean age and BMI were 51 ± 4.6 years and 30 ± 1.4 kg/m2 , respectively. An average 4.5 ± 0.5 cm of IJV was taken, and anastomosed exsitu, end to end to the renal vein. One patient developed a perinephric hematoma requiring reexploration and another expired during follow-up from septic shock of unknown etiology; there were no harvest site complications or deep vein thrombosis. All had immediate and stable graft function at 3.8 ± 1.7 (range: 0.7-11.3) months follow-up. Mean serum creatinine and estimated glomerular filtration rate were 1.3 ± 0.1 mg/dL and 55 ± 2.4 mL/min/1.73 m2 , respectively. Internal jugular vein extension of short right renal veins for kidney transplant is a viable technique for ESRD patients with promising results.

Patients with end-stage lung disease complicated by cirrhosis are not expected to survive lung transplantation alone. Such patients are potential candidates for combined lung-liver transplantation (CLLT), however few reports document the indications and outcomes after CLLT. This is a review of a large single-center CLLT series. Eight consecutive CLLT performed during 2009-2012 were retrospectively reviewed. One patient received a third simultaneous heart transplant. Mean age was 42.5 611.5 years. Pulmonary indications included cystic fibrosis (CF) (n 53), idiopathic pulmonary fibrosis (n 52), a1-antitrypsin deficiency (AATD) (n 51) and pulmonary hypertension (n 52). Liver indications were CF (n 53), hepatitis C (n 52), AATD (n 51), cryptogenic (n 51), and cardiac=congestive (n 51). Urgency was reflected by median lung allocation score (LAS) of 41 (36.0-89.0) and median predicted FEV1 of 25.7%. Median donor age was 25 (20-58) years with median cold ischemia times of 147 minutes and 6.1 hours for lung and liver, respectively. Overall patient survival at 30 days, 90 days and 1 year was 87.5%, 75.0% and 71.4% respectively. One patient had evidence of acute lung rejection, and no patients had liver allograft rejection. Early postoperative mortalities (90 days) were caused by sepsis in 2 recipients who exhibited the highest LAS of 69.9 and 89.0. The remaining recipients had a median LAS of 39.5 and 100% survival at 1-year. Median length of stay was 25 days (7-181). Complications requiring operative intervention included bile duct ischemia (n 51) and bile leak (n 51), ischemia of the bronchial anastomosis (n 51), and necrotizing pancreatitis with duodenal perforation (n 51). This series reflects a large single-center CLLT experience. Sepsis is the most common cause of death. The procedure should be considered for candidates with LAS

METHODS: iPad Minis were distributed to all general surgery residents at a single institution based on a resident-initiated effort to enhance hospital-based workflow. An educational program before tablet distribution highlighted resident-endorsed applications. Technical assistance was provided to establish EMR access. After 18 months (6 months for interns), residents’ use and attitudes toward the tablet were collected via a 31-item paper survey.

Background As national quality initiatives are increasing requirements for individual physician data, our department of surgery initiated a surgeon-specific reporting (SSR) program to assess the value of personal knowledge on individual performance quality. We sought to evaluate the use of SSR as a tool to enable surgeons to assess and improve their clinical performance, and to identify barriers to use of their reports. Study Design Qualitative research design involving semistructured interviews of surgeons who received performance reports derived from National Surgical Quality Improvement Program (NSQIP), Surgical Care Improvement Project (SCIP), and the Centers for Medicare and Medicaid Services (CMS) core measures and hospital administrative data. Transcripts were analyzed by the constant comparative method. Results Twenty-four of 39 surgeons (61.5%) who received their SSRs agreed to be interviewed and 23 were interviewed. About half (11 of 23) demonstrated comprehension of the data validity, accuracy, or complexity. Of these, 6 took steps to validate data or improve performance. Most respondents believed SSR would lead to performance improvement through knowledge of personal outcomes and peer comparison; however, they perceived SSR had limitations, such as small sample size and potential coding errors, and could lead to unintended consequences, such as inaccurate interpretation by others and surgeons' aversion to selecting high-risk patients. Respondents also suggested logistical improvements to reporting methods, such as report format and definitions of metrics. Conclusions Surgeon-specific reporting has the potential to empower surgeons to improve their practice; however, more surgeons need efficient guidelines to understand the metrics. Our findings can be used to guide development of more SSR programs. Whether SSR programs lead to improvements in surgical outcomes is a matter for future research.