Project description:BackgroundBiopsy of a transplanted pancreas is sometimes necessary in patients who have undergone simultaneous pancreas-kidney (SPK) transplantation and have elevated serum lipase and amylase concentrations. However, the risks associated with pancreatic graft biopsy are high, and the best biopsy technique for different location of pancreatic graft remains unclear.MethodsDepending on the anatomical location of the transplanted pancreas, percutaneous computed tomography (CT) combined with color Doppler-guided puncture biopsy or laparoscopic biopsy was used to obtain samples of transplanted pancreatic tissue that were shallow and deep, respectively.ResultsAfter SPK transplantation, 4 patients developed abnormal serum lipase and amylase concentrations and underwent pancreas graft biopsy, 1 patient underwent percutaneous CT combined with color Doppler-guided puncture biopsy, 2 patients underwent laparoscopic wedge biopsy, and 1 patient underwent laparoscopic and puncture biopsy. All biopsies were performed successfully, with no intra- or postoperative complications (e.g., bleeding, pancreatic leakage, intestinal leakage). Biopsy sampling was effective in 3 patients, including 1 case of acute pancreatic rejection, 1 case of pancreatitis, and 1 case of pancreatic plasmablastic lymphoma. Biopsy failed to retrieve samples in 1 patient with a deep pancreatic graft who underwent laparoscopic wedge biopsy.ConclusionsPancreas graft biopsy is safe and feasible after SPK transplantation. In addition to the two biopsy methods mentioned, other methods can also be used. Different biopsy strategies should be formulated according to the anatomical location of the transplanted pancreas.
Project description:BackgroundRisk indices such as the pancreas donor risk index (PDRI) and pre-procurement pancreas allocation suitability score (P-PASS) are utilised in solid pancreas transplantation however no review has compared all derived and validated indices in this field. We systematically reviewed all risk indices in solid pancreas transplantation to compare their predictive ability for transplant outcomes.MethodsMedline Plus, Embase and the Cochrane Library were searched for studies deriving and externally validating risk indices in solid pancreas transplantation for the outcomes of pancreas and patient survival and donor pancreas acceptance for transplantation. Results were analysed descriptively due to limited reporting of discrimination and calibration metrics required to assess model performance.ResultsFrom 25 included studies, discrimination and calibration metrics were only reported in 88% and 38% of derivation studies (n = 8) and in 25% and 25% of external validation studies (n = 12) respectively. 21 risk indices were derived with mild to moderate ability to predict risk (C-statistics 0.52-0.78). Donor age, donor body mass index (BMI) and donor gender were the commonest covariates within derived risk indices. Only PDRI and P-PASS were subsequently externally validated, with variable association with post-transplant outcomes. P-PASS was not associated with pancreas graft survival.ConclusionMost of the risk indices derived for use in solid pancreas transplantation were not externally validated (90%). PDRI and P-PASS are the only risk indices externally validated for solid pancreas transplantation, and when validated without reclassification measures, are associated with 1-year pancreas graft survival and donor pancreas acceptance respectively. Future risk indices incorporating recipient and other covariates alongside donor risk factors may have improved predictive ability for solid pancreas transplant outcomes.
Project description:BackgroundExpanded criteria donor (ECD) kidneys are associated with higher graft loss rates than standard criteria donor kidneys. We sought to determine factors associated with early graft loss and their discrimination ability for this outcome compared with kidney donor risk index.MethodsData were extracted from the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) for ECD transplants between 1997 and 2014. The primary outcome was early graft loss (all-cause graft loss within 3 y of transplantation). Death-censored graft loss was substituted as a sensitivity analysis. Era-adjusted odds ratios were calculated by multivariable logistic regression for donor, recipient, and transplant factors available at transplantation. Discrimination was assessed by c-statistic, with 95% confidence intervals (CIs) calculated by bootstrapping.ResultsOf 2152 ECD kidney transplants, early graft loss occurred in 406 (19%) and was associated with recipient diabetes, smoking, First Nations recipients, and oliguria. Of factors defining ECD (age, elevated terminal creatinine, hypertension, death from cerebrovascular accident), all but mode of death were associated with early graft loss. The multivariable model, including known donor, recipient, and transplant factors, was moderately good at predicting early graft loss (c-statistic 0.65; 95% CI, 0.62-0.68). Recipient factors (c-statistic 0.62; 95% CI, 0.59-0.65) performed equally well compared with donor factors (c-statistic 0.60; 95% CI, 0.57-0.64) or the kidney donor risk index (c-statistic 0.60; 95% CI, 0.56-0.63).ConclusionsEarly graft loss occurs in approximately one-fifth of ECD kidney transplants. The discriminatory value of commonly used recipient, donor, and transplant factors are approximately comparable and limited.
Project description:The early detection of graft failure in pediatric liver transplantation is crucial for appropriate intervention. Graft failure is associated with numerous perioperative risk factors. This study aimed to develop an individualized predictive model for 90-days graft failure in pediatric liver transplantation using machine learning methods. We conducted a single-center retrospective cohort study. A total of 87 liver transplantation cases performed in patients aged < 12 years at the Severance Hospital between January 2010 and September 2020 were included as data samples. Preoperative conditions of recipients and donors, intraoperative care, postoperative serial laboratory parameters, and events observed within seven days of surgery were collected as features. A least absolute shrinkage and selection operator (LASSO) -based method was used for feature selection to overcome the high dimensionality and collinearity of variables. Among 146 features, four variables were selected as the resultant features, namely, preoperative hepatic encephalopathy, sodium level at the end of surgery, hepatic artery thrombosis, and total bilirubin level on postoperative day 7. These features were selected from different times and represent distinct clinical aspects. The model with logistic regression demonstrated the best prediction performance among various machine learning methods tested (area under the receiver operating characteristic curve (AUROC) = 0.898 and area under the precision-recall curve (AUPR) = 0.882). The risk scoring system developed based on the logistic regression model showed an AUROC of 0.910 and an AUPR of 0.830. Together, the prediction of graft failure in pediatric liver transplantation using the proposed machine learning model exhibited superior discrimination power and, therefore, can provide valuable information to clinicians for their decision making during the postoperative management of the patients.
Project description:BackgroundPancreas transplant alone (PTA) recipients are more affected by pancreas graft thrombosis, and graft loss compared to simultaneous pancreas-kidney (SPK) recipients. The pathophysiology is unknown, but an increased immune response has been suggested in the PTA recipients. In this observational study, we compared perioperative thromboinflammation between PTA (n=32) and SPK (n=35) recipients, and between PTA recipients with (n=14) versus without (n=18) early graft thrombosis.MethodsWe measured C-reactive protein (CRP), plasma markers of activated coagulation and complement, and cytokines preoperatively and daily during the first postoperative week.ResultsPreoperatively, coagulation and complement activation markers were comparable between PTA and SPK recipients, while cytokine concentrations were higher in SPK recipients (TNF, IL-8, IP-10, MCP-1, MIP-1α; all p<0.05). On the first postoperative day, PTA recipients had higher coagulation activation, measured as thrombin-antithrombin complex (TAT), than SPK recipients (p=0.008). In the first postoperative week, PTA recipients showed higher relative cytokine release (IL-6, IL-8, G-CSF, IP-10, MCP-1, and MIP-1α; all p<0.05) while SPK recipients showed higher absolute cytokine concentrations (TNF, IL-1ra, IL-8, MIP-1α, and IL-4; all p<0.05). PTA and SPK recipients showed similar terminal complement complex (TCC, sC5b-9) activation. On the first postoperative day, TCC (OR 1.2 [95% CI 1.0-1.5] for 0.1 CAU/ml increase, p=0.02) and CRP (OR 1.2 [95% CI 1.0-1.3] for 10 mg/L increase, p=0.04) were associated with an increased risk of early graft thrombosis. TCC was specific for graft thrombosis, while CRP increased with several complications. PTA recipients with compared to those without graft thrombosis had higher TCC pre- (p=0.04) and postoperatively (p=0.03).ConclusionThe relative increase in postoperative thromboinflammatory response was more pronounced in PTA recipients. Complement activation was associated with an increased risk of graft thrombosis. This study indicates that innate immune activation rather than elevated levels may affect early postoperative pancreas graft thrombosis.Clinical trial registrationhttps://clinicaltrials.gov/ct2/show/NCT01957696, identifier NCT01957696.
Project description:Background: There is paucity of data in the available medical literature regarding the parameters of the volumetric perfusion of pancreas grafts. Methods: From 5 February 2016 to 23 December 2021, we performed perfusion computed tomography in 41 patients at different times after simultaneous pancreas and kidney transplantation. The study group consisted of 18 men (44%) and 23 women (56%) with a long history of type 1 diabetes mellitus complicated by terminal chronic renal failure. The results of the perfusion computed tomography of the pancreas graft were studied, and the effects of post-transplantation timing and graft revascularization peculiarities on volumetric perfusion parameters were evaluated. Results: The median arterial blood flow, arterial blood volume, and permeability of the pancreas graft were 115.1 [99.7;130.3] mL/100 mL/min, 46.7 [37.4;56.9] mL/min, and 8.6 [4.1;11.4] mL/100 mL/min, respectively. No statistically significant differences in the averaged perfusion values were found in the head, body, and tail of the pancreas graft. The post-transplantation timing and the number of arteries involved in graft revascularization did not have a significant effect on the volumetric perfusion of the graft. Conclusion: The volumetric perfusion results of the pancreas graft correspond to those obtained in the study of pancreatic perfusion in healthy participants.
Project description:BackgroundGraft thrombosis is the main cause of early graft loss following pancreas transplantation, and is more frequent in pancreas transplant alone (PTA) compared with simultaneous pancreas-kidney (SPK) recipients. Ischemia-reperfusion injury during transplantation triggers a local thromboinflammatory response. We aimed to evaluate local graft inflammation and its potential association with early graft thrombosis.MethodsIn this observational study, we monitored 67 pancreas-transplanted patients using microdialysis catheters placed on the pancreatic surface during the first postoperative week. We analyzed 6 cytokines, interleukin-1 receptor antagonist (IL-1ra), IL-6, IL-8, interferon gamma-induced protein 10 (IP-10), macrophage inflammatory protein 1β (MIP-1β), IL-10, and the complement activation product complement activation product 5a (C5a) in microdialysis fluid. We compared the dynamic courses between patients with pancreas graft thrombosis and patients without early complications (event-free) and between PTA and SPK recipients. Levels of the local inflammatory markers, and plasma markers C-reactive protein, pancreas amylase, and lipase were evaluated on the day of thrombosis diagnosis compared with the first week in event-free patients.ResultsIL-10 and C5a were not detectable. Patients with no early complications (n = 34) demonstrated high IL-1ra, IL-6, IL-8, IP-10, and MIP-1β concentrations immediately after surgery, which decreased to steady low levels during the first 2 postoperative days (PODs). Patients with early graft thrombosis (n = 17) demonstrated elevated IL-6 (P = 0.003) concentrations from POD 1 and elevated IL-8 (P = 0.027) concentrations from POD 2 and throughout the first postoperative week compared with patients without complications. IL-6 (P < 0.001) and IL-8 (P = 0.003) were higher on the day of thrombosis diagnosis compared with patients without early complications. No differences between PTA (n = 35) and SPK (n = 32) recipients were detected.ConclusionsLocal pancreas graft inflammation was increased in patients experiencing graft thrombosis, with elevated postoperative IL-6 and IL-8 concentrations, but did not differ between PTA and SPK recipients. Investigating the relationship between the local cytokine response and the formation of graft thrombosis warrants further research.
Project description:BACKGROUND: Hepatic osteodystrophy occurs in the majority of patients with advanced chronic liver disease with the abnormalities in bone metabolism accelerating following orthotopic liver transplantation (OLT). AIMS: To examine changes in bone mineral density (BMD) following OLT and to investigate factors that lead to bone loss. METHODS: Twelve patients had BMD (at both the lumbar spine (LS) and femoral neck (FN)) and biochemical markers measured preoperatively and for 24 months following OLT. RESULTS: BMD was low in 75% of patients prior to OLT and decreased significantly from baseline at the LS at three months and the FN at six months. BMD began to increase thereafter at both sites, approaching baseline values at the LS by 12 months. Bone formation markers, osteocalcin and procollagen type I carboxy propeptide, decreased immediately post-OLT, with a concomitant increase seen in the resorption markers pyridinoline and deoxypyridinoline. This resulted in a negative uncoupling index early post-OLT, that rebounded to positive values after six months. There was a significant correlation between the change in the uncoupling index between six and three months which preceded the increase in BMD at 12 months. The decrease in BMD recorded early post-OLT correlated with vitamin D levels at three months. CONCLUSIONS: Results suggest that increased resorption and inadequate formation are the major contributors to additional bone loss following OLT. Non-invasive biochemical markers precede later changes in BMD in this patient group following OLT and may have a role in investigating and planning intervention strategies to prevent bone loss in future studies.
Project description:The sequence of graft implantation in simultaneous pancreas-kidney transplantation (SPKT) warrants additional study and more targeted focus, since little is known about the short- and long-term effects on the outcome and graft survival after transplantation. 103 patients receiving SPKT in our department between 1999 and 2015 were included in the study. Patients were divided according to the sequence of graft implantation into pancreas-first (PF, n = 61) and kidney-first (KF, n = 42) groups. Clinicopathological characteristics, outcome and survival were reviewed retrospectively. Donor and recipient characteristics were similar. Rates of post-operative complications and graft dysfunction were significantly higher in the PF group compared with the KF group (episodes of acute rejection within the first year after SPKT: 11 (18%) versus 2 (4.8%); graft pancreatitis: 18 (18%) versus 2 (4.8%), p = 0.04; vascular thrombosis of the pancreas: 9 (14.8%) versus 1 (2.4%), p = 0.03; and delayed graft function of the kidney: 12 (19.6%) versus 2 (4.8%), p = 0.019). The three-month pancreas graft survival was significantly higher in the KF group (PF: 77% versus KF: 92.1%; p = 0.037). No significant difference was observed in pancreas graft survival five years after transplantation (PF: 71.6% versus KF: 84.8%; p = 0.104). Kidney graft survival was similar between the two groups. Multivariate analysis revealed order of graft implantation as an independent prognostic factor for graft survival three months after SPKT (HR 2.6, 1.3-17.1, p = 0.026) and five years (HR 3.7, 2.1-23.4, p = 0.040). Our data indicates that implantation of the pancreas prior to the kidney during SPKT has an influence especially on the early-post-operative outcome and survival rate of pancreas grafts.
Project description:BackgroundRacial disparities following pancreas transplantation (PTX) are poorly defined.MethodsThis was a large-scale, single-center, longitudinal cohort study including adult PTX recipients. Patients were grouped by race to allow for comparisons.Results287 PTX recipients were included; 125 (43.5%) were African American (AA). At baseline, AAs had a significantly higher proportion of T2DM (19.4% vs. 5.7%, p = 0.001), were younger, and more likely to be female. AAs experienced significantly higher rates of pancreatic leaks and post-operative bleeding. PTX rejection was comparable, however, kidney rejection tended to be higher among AA SPKs. Long-term mean HgbA1C levels were significantly higher among AAs (6.9% vs. 6.3%, p = 0.039). Patient and graft survival was comparable between groups, but early patient survival tended to be lower in AAs.ConclusionsThis study demonstrated significant perioperative health disparities among AA PTX recipients, including poorer glycemic control and more early deaths, despite similar long-term patient and graft survival.