Impact of Perioperative Prophylaxis With Enterococcus Activity on Risk of Surgical-Site Infection After Pancreas Transplantation.

Surgical-site infection (SSI) is the most common early infectious complication after pancreas transplantation (PT). Although SSI has been shown to worsen outcomes, little data exist to guide optimal choices in perioperative prophylaxis. Methods: We performed a retrospective cohort study of PT recipients from 2010-2020 to examine the effect of perioperative antibiotic prophylaxis with Enterococcus coverage. Enterococcus coverage included antibiotics that would be active for penicillin-susceptible Enterococcus isolates. The primary outcome was SSI within 30 d of transplantation, and secondary outcomes were Clostridioides difficile infection (CDI) and a composite of pancreas allograft failure or death. Outcomes were analyzed by multivariable Cox regression. Results: Of 477 PT recipients, 217 (45.5%) received perioperative prophylaxis with Enterococcus coverage. Eighty-seven recipients (18.2%) developed an SSI after a median of 15 d from transplantation. In multivariable Cox regression analysis, perioperative Enterococcus prophylaxis was associated with reduced risk of SSI (hazard ratio [HR] 0.58; 95% confidence interval [CI], 0.35-0.96; P = 0.034). Anastomotic leak was also significantly associated with elevated risk of SSI (HR 13.95; 95% CI, 8.72-22.32; P < 0.001). Overall, 90-d CDI was 7.4%, with no difference between prophylaxis groups (P = 0.680). SSI was associated with pancreas allograft failure or death, even after adjusting for clinical factors (HR 1.94; 95% CI, 1.16-3.23; P = 0.011). Conclusions: Perioperative prophylaxis with Enterococcus coverage was associated with reduced risk of 30-d SSI but did not seem to influence risk of 90-d CDI after PT. This difference may be because of the use of beta-lactam/beta-lactamase inhibitor combinations, which provide better activity against enteric organisms such as Enterococcus and anaerobes compared with cephalosporin. Risk of SSI was also related to anastomotic leak from surgery, and SSI itself was associated with subsequent risk of a poor outcome. Measures to mitigate or prevent early complications are warranted.

Dysregulated metabolism of the late herpes simplex virus 1 transcriptome through the vhs-VP22 axis uncouples virus cytopathic effect and virus production.

Herpes simplex virus 1 (HSV1) expresses its genes in a classical cascade culminating in the production of large amounts of structural proteins to facilitate virus assembly. HSV1 lacking the virus protein VP22 (Δ22) exhibits late translational shutoff, a phenotype that has been attributed to the unrestrained activity of the virion host shutoff (vhs) protein, a virus-encoded endoribonuclease which induces mRNA degradation during infection. We have previously shown that vhs is also involved in regulating the nuclear-cytoplasmic compartmentalisation of the virus transcriptome, and in the absence of VP22 a number of virus transcripts are sequestered in the nucleus late in infection. Here we show that despite expressing minimal amounts of structural proteins and failing to plaque on human fibroblasts, the strain 17 Δ22 virus replicates and spreads as efficiently as Wt virus, but without causing cytopathic effect (CPE). Nonetheless, CPE-causing virus spontaneously appeared on Δ22-infected human fibroblasts, and four viruses isolated in this way had all acquired point mutations in vhs which rescued late protein translation. However, unlike a virus deleted for vhs, these viruses still induced the degradation of both cellular and viral mRNA suggesting that vhs mutation in the absence of VP22 is necessary to overcome a more complex disturbance in mRNA metabolism than mRNA degradation alone. The ultimate outcome of secondary mutations in vhs is therefore the rescue of virus-induced CPE caused by late protein synthesis, and while there is a clear selective pressure on HSV1 to mutate vhs for optimal production of late structural proteins, the purpose of this is over and above that of virus production.

Personalized Pre-clinic Nursing Telemedicine Visit: An Efficient and Efficacious Approach for Bowel and Bladder Dysfunction in Children.

OBJECTIVES: To evaluate the effectiveness and efficacy of a Registered Nurse (RN) led educational pre-clinic telephone call on compliance and outcomes in children with bowel and bladder dysfunction (BBD). METHODS: A retrospective chart review of a prospectively applied protocol in a single academic institution was performed for children aged 4-17 presenting with BBD. All children underwent a pre-clinic RN telemedicine visit where they were educated on pathophysiology of BBD, provided personalized urotherapy and bowel recommendations and instructed to complete pre-clinic questionnaires and voiding diaries. Patients were evaluated by a provider 4weeks following RN call. Data collected included compliance with forms, bowel management and need for imaging/testing, medications, and biofeedback. Patients were considered to improve with urotherapy alone if they were discharged from urology without the need for medications and/or biofeedback. RESULTS: In total, 277 patients completed an RN call and 224 patients attended a provider visit between December 2020 and June 2022. Mean age was 9.4years (3:1 Female to Male ratio). During the RN call, 154 (56%) patients had bowel management initiated. Of the 224 patients seen by a provider, 69% (n = 154) had symptom improvement or resolution with urotherapy alone. Thirty-eight patients (17%) enrolled in biofeedback with 7 (3%) completing all 8 sessions. Thirty-two patients (14%) required medication for daytime bladder symptoms. CONCLUSION: Our novel RN-led pre-clinic telemedicine visit demonstrates excellent compliance and patient outcomes for children with BBD and can reduce the use of unnecessary imaging, medications, and time-consuming treatments such as biofeedback.

Development of a portable abdominal normothermic regional perfusion (A-NRP) program in the United States.

In situ abdominal normothermic regional perfusion (A-NRP) has been used for liver transplantation (LT) with donation after circulatory death (DCD) liver grafts in Europe with excellent results; however, adoption of A-NRP in the United States has been lacking. The current report describes the implementation and results of a portable, self-reliant A-NRP program in the United States. Isolated abdominal in situ perfusion with an extracorporeal circuit was achieved through cannulation in the abdomen or femoral vessels and inflation of a supraceliac aortic balloon and cross-clamp. The Quantum Transport System by Spectrum was used. The decision to use livers for LT was made through an assessment of perfusate lactate (q15min). From May to November 2022, 14 A-NRP donation after circulatory death procurements were performed by our abdominal transplant team (N = 11 LT, N = 20 kidney transplants, and 1 kidney-pancreas transplant). The median A-NRP run time was 68 minutes. None of the LT recipients had post-reperfusion syndrome, nor were there any cases of primary nonfunction. All livers were functioning well at the time of maximal follow-up with zero cases of ischemic cholangiopathy. The current report describes the feasibility of a portable A-NRP program that can be used in the United States. Excellent short-term post-transplant results were achieved with both livers and kidneys procured from A-NRP.

Mayo Adhesive Probability (MAP) score of non-donated kidney aids in predicting post-operative renal function following donor nephrectomy.

BACKGROUND: To examine the association of preoperative Mayo Adhesive Probability (MAP) scores in the donor (MAPd) and non-donor kidneys (MAPnd) with post-donation renal function. METHODS: Three hundred thirty-one patients undergoing hand assisted laparoscopic donor nephrectomy (HALDN) were reviewed. MAPd and MAPnd were obtained. Estimated glomerular filtration rate (eGFR) was recorded preoperatively and at 1 day, 1 month, and 6 months postoperatively. RESULTS: Two hundred females and 131 males were evaluated with median BMI 26.4 kg/m2 (range 17.1-39.6) and median age 45 years (range 19-78). MAPd score was 0 for 231 patients (69.8%) and > 0 for 100 patients (30.2%). MAPnd score was 0 for 234 patients (70.7%) and > 0 for 97 patients (29.3%). The median preoperative eGFR was 86.6 ml/min/1.73m2 (range 48.8-138.4). After adjusting for preoperative eGFR, BMI, ASA score, and kidney sidedness, postoperative eGFR was associated with MAP score in the non-donated kidney (p = 0.014) but not in the donated kidney (p = 0.24). Compared to donors with MAPnd = 0, donors with a MAPnd > 0, mean eGFR was - 2.33 ml/min/1.73m2 lower at postoperative day 1 (95% CI - 4.24 to - 0.41, p = 0.018), - 3.02 ml/min/1.73m2 lower at 1 month (95% CI - 5.11 to - 0.93, p = 0.005), and - 2.63 ml/min/1.73m2 lower at 6 months postoperatively (95% CI - 5.01 to - 0.26, p = 0.030). CONCLUSIONS: MAP score > 0 in the non-donated kidney is associated with worse renal function in the 6 months following HALDN.

Intraoperative Events in Liver Transplantation Using Donation After Circulatory Death Donors.

Liver grafts from donation after circulatory death (DCD) are a source of organs to decrease wait-list mortality. While there have been lower rates of graft loss, there are concerns of an increased incidence of intraoperative events in recipients of DCD grafts. We aim to look at the incidence of intraoperative events between recipients of livers from DCD and donation after brain death (DBD) donors. We collected data for 235 DCD liver recipients between 2006 and 2017. We performed a 1:1 propensity match between these patients and patients with DBD donors. Variables included recipient age, liver disease etiology, biological Model for End-Stage Liver Disease (MELD) score, allocation MELD score, diagnosis of hepatocellular carcinoma, and year of transplantation. DCD and DBD groups had no significant differences in incidence of postreperfusion syndrome (P = 0.75), arrhythmia requiring cardiopulmonary resuscitation (P = 0.66), and treatments for hyperkalemia (P = 0.84). In the DCD group, there was a significant increase in amount of total intraoperative and postreperfusion blood products (with exception of postreperfusion packed red blood cells) utilized (P < 0.05 for all products), significant differences in postreperfusion thromboelastography parameters, as well as inotropes and vasopressors used (P < 0.05 for all infusions). There was no difference in patient (P = 0.49) and graft survival (P = 0.10) at 1, 3, and 5 years. In conclusion, DCD grafts compared with a cohort of DBD grafts have a similar low incidence of major intraoperative events, but increased incidence of transient vasopressor/inotropic usage and increased blood transfusion requirements. This does not result in differences in longterm outcomes. While centers should continue to look at DCD liver donors, they should be cognizant regarding intraoperative care to prevent adverse outcomes.

Establishment of Systems to Enable Isolation of Porcine Monoclonal Antibodies Broadly Neutralizing the Porcine Reproductive and Respiratory Syndrome Virus.

The rapid evolution of porcine reproductive and respiratory syndrome viruses (PRRSV) poses a major challenge to effective disease control since available vaccines show variable efficacy against divergent strains. Knowledge of the antigenic targets of virus-neutralizing antibodies that confer protection against heterologous PRRSV strains would be a catalyst for the development of next-generation vaccines. Key to discovering these epitopes is the isolation of neutralizing monoclonal antibodies (mAbs) from immune pigs. To address this need, we sought to establish systems to enable the isolation of PRRSV neutralizing porcine mAbs. We experimentally produced a cohort of immune pigs by sequential challenge infection with four heterologous PRRSV strains spanning PRRSV-1 subtypes and PRRSV species. Whilst priming with PRRSV-1 subtype 1 did not confer full protection against a subsequent infection with a PRRSV-1 subtype 3 strain, animals were protected against a subsequent PRRSV-2 infection. The infection protocol resulted in high serum neutralizing antibody titers against PRRSV-1 Olot/91 and significant neutralization of heterologous PRRSV-1/-2 strains. Enriched memory B cells isolated at the termination of the study were genetically programmed by transduction with a retroviral vector expressing the Bcl-6 transcription factor and the anti-apoptotic Bcl-xL protein, a technology we demonstrated efficiently converts porcine memory B cells into proliferating antibody-secreting cells. Pools of transduced memory B cells were cultured and supernatants containing PRRSV-specific antibodies identified by flow cytometric staining of infected MARC-145 cells and in vitro neutralization of PRRSV-1. Collectively, these data suggest that this experimental system may be further exploited to produce a panel of PRRSV-specific mAbs, which will contribute both to our understanding of the antibody response to PRRSV and allow epitopes to be resolved that may ultimately guide the design of immunogens to induce cross-protective immunity.

The Association of the Mayo Adhesive Probability (MAP) Score With Total Operative Time in Patients Undergoing Hand-assisted Laparoscopic Donor Nephrectomy.

OBJECTIVE: To assess whether donor kidney Mayo Adhesive probability (MAP) score is associated with (total operative time) ORT in patients undergoing hand-assisted laparoscopic donor nephrectomy (HALDN). METHODS: Three hundred and thirty-one patients undergoing HALDN were reviewed. Donor kidney MAP scores were recorded based on preoperative computed tomography or magnetic resonance imaging. Single variable and multiple variable regression analysis were used to evaluate the correlation between MAP score and ORT. RESULTS: Three hundred and thirty-one patients underwent HALDN between January 2007 and April 2017. Median body mass index was 26.4 kg/m2 (interquartile range 23.4, 29.5) and median age at time of surgery was 45 years (interquartile range 37, 53). Two hundred and thirty-one patients had donor kidney MAP = 0. Hundred patients had donor kidney MAP >0. Mean ORT was 163 minutes for females with MAP = 0 and 166 minutes for females with MAP >0. Median ORT was 180 minutes for males with MAP =0 and 191 minutes for males with MAP >0. Donor kidney MAP score > 0 was significantly correlated with longer ORT (increase of 24.4 minutes, P = .001) in single variable analysis. In multivariable analysis, this correlation was only significant for males (increase of 28.9 minutes, P = .013). CONCLUSION: MAP score > 0 is associated with longer ORT for males undergoing HALDN.

Looking inward: The impact of operative time on graft survival after liver transplantation.

BACKGROUND: Operative time often has been cited as an important factor for postoperative outcomes. Despite this belief, most efforts to improve liver transplant outcomes have largely focused on only patient and donor factors, and little attention has been paid on operative time. The primary objective of this project was to determine the impact of operative time on graft survival after liver transplant. METHODS: A retrospective review of 2,877 consecutive liver transplants performed at a single institution was studied. Data regarding recipient, donor, and operative characteristics, including detailed granular operative times were collected prospectively and retrospectively reviewed. Using an instrument variable approach, Cox multivariate modeling was performed to assess the impact of operative time without the confounding of known and unknown variables. RESULTS: Of the 2,396 patients who met the criteria for review, the most important factors determining liver transplant graft survival included recipient history of Hepatitis C (hazard ratio 1.45, P = .02), donor age (hazard ratio 1.23, P = .03), use of liver graft from donation after cardiac death donor (hazard ratio 1.50, P < .01), and operative time (hazard ratio 1.26, P = .01). In detailed analysis of stages of the liver transplant operation, the time interval from incision to anhepatic phase was associated with graft survival (hazard ratio 1.33; P = .02). CONCLUSION: Using a novel instrument variable approach, we demonstrate that operative time (in particular, the time interval from incision to anhepatic time) has a significant impact on graft survival. It also seems that some of this efficiency is under the influence of the transplant surgeon.

Comparison of longterm outcomes and quality of life in recipients of donation after cardiac death liver grafts with a propensity-matched cohort.

The use of liver grafts from donation after cardiac death (DCD) has been limited due to the increased rate of graft failure, mostly related to ischemic cholangiopathy (IC). It is our hypothesis that longterm outcomes and quality of life (QOL) similar to patients undergoing liver transplantation (LT) with donation after brain death (DBD) can be achieved. Clinical outcomes of all patients undergoing DCD LT (n = 300) between 1998 and 2015 were compared with a propensity score-matched cohort of patients undergoing DBD LT (n = 300). Patients were contacted for a follow-up questionnaire and short-form (SF)-12 QOL Survey administration. Median follow-up was >5 years. Graft survival at 1-, 3-, and 5-years was 83.8%, 75.5%, and 70.1% in the DCD LT group and 88.4%, 80.3%, and 73.9% in the DBD LT group (P = 0.27). Patient survival at 1-, 3-, and 5-years was 92.3%, 86.1%, and 80.3% in the DCD LT group and 92.3%, 85.1%, and 79.5% in the DBD LT group (P = 0.81). IC developed in 11.7% and 2% of patients in the DCD LT group and DBD LT group, respectively (P < 0.001). DCD LT recipients who developed IC had inferior graft survival compared with both the DCD non-IC group (P < 0.001) and the DBD LT group (P < 0.001); no difference in graft survival was observed between the DCD non-IC group and the DBD LT group (P = 0.50). Physical and Mental Composite Scores on the SF-12 QOL questionnaire were similar between the DCD LT and DBD LT groups (44.0 versus 45.4; P = 0.34 and 51.9 versus 52.2; P = 0.83), respectively. Similar longterm survival and QOL scores can be achieved between DCD LT and DBD LT. Prevention of IC in DCD LT yields excellent graft and patient survival with virtually no difference compared with DBD LT. Liver Transplantation 23 342-351 2017 AASLD.

Simultaneous liver and kidney transplantation in elderly patients: Outcomes and validation of a clinical risk score for patient selection.

 Introduction and aim. Many transplant programs have expanded eligibility to include patients previously ineligible because of advanced age. Outcomes of simultaneous liver-kidney transplantation (SLK) in recipients with advanced age are not known. MATERIAL AND METHODS: Data from patients undergoing transplantation between 2002 and 2015 were obtained from the UNOS Standard Analysis and Research file. RESULTS: SLK recipients aged ≥ 65 years (N = 677), SLK recipients aged < 65 years (N = 4517), and recipients of liver transplant alone(LTA) aged ≥ 65 years(N = 8495) were compared. Recipient characteristics were similar between the SLK groups. Similar patient and graft survival were observed in SLK recipients aged ≥ 65 years compared to SLK recipients aged < 65 years and LTA recipients aged ≥ 65 years. Importantly, in a subgroup analysis, superior survival was seen in the SLK group aged ≥ 65 years compared to LTA recipients aged ≥ 65 years who underwent dialysis in the week prior to transplantation (p < 0.001). A prediction model of patient survival was developed for the SLK group aged ≥ 65 years with predictors including: age ≥ 70 years (3 points), calculated MELD score (-1 to 2 points), and recipient ventilator status at the time of SLK (4 points). The risk score predicted patient survival, with a significantly inferior survival seen in patients with a score ≥ 4 (p < 0.001). CONCLUSIONS: Age should not be used as a contraindication for SLK transplantation. The validated scoring system provides a guide for patient selection and can be used when evaluating elderly patients for SLK transplantation listing.

Outcomes of liver transplantation with liver grafts from pediatric donors used in adult recipients.

Although there is an agreement that liver grafts from pediatric donors (PDs) should ideally be used for pediatric patients, there remain situations when these grafts are turned down for pediatric recipients and are then offered to adult recipients. The present study aimed to investigate the outcomes of using these grafts for liver transplantation (LT) in adult patients. Data from all patients undergoing LT between 2002 and 2014 were obtained from the United Network for Organ Sharing Standard Analysis and Research file. Adult recipients undergoing LT were divided into 2 groups: those receiving a pediatric liver graft (pediatric-to-adult group) and those receiving a liver graft from adult donors (adult-to-adult group). A separate subgroup analysis comparing the PDs used for adult recipients and those used for pediatric recipients was also performed. Patient and graft survival were not significantly different between pediatric-to-adult and adult-to-adult groups (P = 0.08 and P = 0.21, respectively). Hepatic artery thrombosis as the cause for graft loss was higher in the pediatric-to-adult group (3.6%) than the adult-to-adult group (1.9%; P < 0.001). A subanalysis looking at the pediatric-to-adult group found that patients with a predicted graft-to-recipient weight ratio (GRWR) < 0.8 had a higher 90-day graft loss rate than those with a GRWR ≥ 0.8 (39% versus 9%; P < 0.001). PDs used for adult recipients had a higher proportion of donors with elevated aspartate aminotransferase/alanine aminotransferase (20% vs. 12%; P < 0.001), elevated creatinine (11% vs. 4%; P < 0.001), donation after cardiac death donors (12% vs. 0.9%; P < 0.001), and were hepatitis B virus core positive (1% vs. 0.3%; P = 0.002) than PDs used for pediatric recipients. In conclusion, acceptable patient and graft survival can be achieved with the use of pediatric liver grafts in adult recipients, when these grafts have been determined to be inappropriate for usage in the pediatric population. Liver Transplantation 22 1099-1106 2016 AASLD.

Atrioventricular Sequential Pacing for Hypertrophic Cardiomyopathy During Liver Transplantation.

Hypertrophic cardiomyopathy is a myocardial disorder that carries an increased risk of morbidity and mortality during liver transplantation. We describe the use of atrioventricular sequential pacing, placed preoperatively, to assist with intraoperative management of a patient with severe refractory hypertrophic cardiomyopathy undergoing orthotopic piggyback liver transplantation. We discuss the pathogenesis and treatment of this infrequent but serious comorbidity.

Patterns and Outcomes Associated with Patient Migration for Liver Transplantation in the United States.

BACKGROUND: Traveling to seek specialized care such as liver transplantation (LT) is a reality in the United States. Patient migration has been attributed to organ availability. The aims of this study were to delineate patterns of patient migration and outcomes after LT. STUDY DESIGN: All deceased donor LT between 2008-2013 were extracted from UNOS data. Migrated patients were defined as those patients who underwent LT at a center in a different UNOS region from the region in which they resided and traveled a distance > 100 miles. RESULTS: Migrated patients comprised 8.2% of 28,700 LT performed. Efflux and influx of patients were observed in all 11 UNOS regions. Regions 1, 5, 6, and 9 had a net efflux, while regions 2, 3, 4, 7, 10, and 11 had a net influx of patients. After multivariate adjustment for donor and recipient factors, graft (p = 0.68) and patient survival (p = 0.52) were similar between migrated and non-migrated patients. CONCLUSION: A significant number of patients migrated in patterns that could not be explained alone by regional variations in MELD score and wait time. Migration may be a complex interplay of factors including referral patterns, specialized services at centers of excellence and patient preference.

A novel objective method for deceased donor and recipient size matching in liver transplantation.

Although the consequences of implantation of a large whole liver graft into a small recipient such as compression and compromise of graft perfusion are well known, no accepted measure to aid in donor-to-recipient size matching exists. Donor liver graft and recipient native liver weights as well as donor and recipient size and amount of ascites were investigated in 1953 patients who underwent liver transplantation using deceased donor grafts between January 2002 and July 2013. We used a previously described formula for liver resections (standardized total liver volume [sTLV] = -794.41 + 1267.28 × body surface area [m(2)]) for calculating sTLV, in the current cohort of deceased liver donors. Early allograft dysfunction (EAD) and graft survival were the primary outcome measures. The formula for calculating sTLV for liver resections was validated as an accurate predictor of liver volume in the current cohort of deceased liver donors (r(2) = 0.45; P < 0.001). A cutoff point of sTLV ratio ≥ 1.25 was determined through receiver operating characteristic curves, and patients were dichotomized into 2 groups. In the sTLV ratio ≥ 1.25 group, 50% of patients developed EAD compared to 25% of patients in the sTLV ratio < 1.25 group (P < 0.001). The proportion of patients developing graft failure within 90 days was 9.6% in the sTLV ratio ≥ 1.25 group and 5.4% in the sTLV ratio < 1.25 group (P = 0.045). This study validates the use of the sTLV for prediction of actual donor liver weight in the transplant setting. Using this formula, donors with a calculated sTLV size ratio ≥ 1.25 have an increased risk of EAD and therefore caution should be used when that value is exceeded. This adjusted size ratio can be used as a decision aid when considering donor and recipient matching with potential liver organ offers.