Disease progression in patients with the restrictive and mixed phenotype of Chronic Lung Allograft dysfunction-A retrospective analysis in five European centers to assess the feasibility of a therapeutic trial

BACKGROUND

Chronic Lung Allograft Dysfunction (CLAD) is a major obstacle for long term survival after lung transplantation (LTx). Besides Bronchiolitis Obliterans Syndrome, two other phenotypes of CLAD, restrictive allograft syndrome (RAS) and mixed phenotype, have been described. Trials to test in these conditions are desperately needed and analyzing natural outcome to plan such trials is essential.

METHODS

We performed a retrospective analysis of functional outcome in bilateral LTx recipients with RAS and mixed phenotype, transplanted between 2009 and 2018 in five large European centers with follow- up spirometry up to 12 months after diagnosis. Based on these data, sample size and power calculations for randomized therapeutic trial was estimated using two imputation methods for missing values.

RESULTS

Seventy patients were included (39 RAS and 31 mixed phenotype), median 3.1 years after LTx when CLAD was diagnosed. Eight, 13 and 25 patients died within 6, 9 and 12 months after diagnosis and a two patients underwent re-transplantation within 12 months leading to a graft survival of 89, 79 and 61% six, nine and 12 months after diagnosis, respectively. Observed FEV1 decline was 451 ml at 6 months and stabilized at 9 and 12 months, while FVC showed continuous decline. Using two methods of imputation, a progressive further decline after 6 months for FEV1 was noted.

CONCLUSION

The poor outcome of these two specific CLAD phenotypes suggests the urgent need for future therapeutic randomized trials. The number of missing values in a potential trial seems to be high and most frequently attributed to death. Survival may be used as an endpoint in clinical trials in these distinct phenotypes and imputation techniques are relevant if graft function is used as a surrogate of disease progression in future trials.

Lung transplantation using allografts with more than 8 hours of ischemic time: A single-institution experience

BACKGROUND

Six hours was historically regarded as the limit of acceptable ischemic time for lung allografts. However, broader sharing of donor lungs often necessitates use of allografts with ischemic time >6 hours. We characterized the association between ischemic time ≥8 hours and outcomes after lung transplantation using a contemporary cohort from a high-volume institution.

METHODS

Patients who underwent primary isolated bilateral lung transplantation between 1/2016 and 5/2020 were included. Patients bridged to transplant with extracorporeal membrane oxygenation or mechanical ventilation, and ex-vivo perfusion cases were excluded. Recipients were stratified by total allograft ischemic time <8 hours (standard) vs ≥8 hours (long). Perioperative outcomes and post-transplant survival were compared between groups.

RESULTS

Of 358 patients, 95 (26.5%) received long ischemic time (≥8 hours) lungs. Long ischemic time recipients were more likely to be male and have donation after circulatory death donors than standard ischemic time recipients. On unadjusted analysis, long and standard ischemic time recipients had similar survival, and similar rates of grade 3 primary graft dysfunction at 72 hours, extracorporeal membrane oxygenation post-transplant, acute rejection within 30 days, reintubation, and post-transplant length of stay. After adjustment, long and standard ischemic time recipients had comparable risks of mortality or graft failure.

CONCLUSIONS

In a modern cohort, use of lung allografts with "long" ischemic time ≥8 hours were associated with acceptable perioperative outcomes and post-transplant survival. Further investigation is required to better understand how broader use impacts post-lung transplant outcomes and the implications for smarter sharing under an evolving national allocation policy.

Mode of Obstetric Delivery in Kidney and Liver Transplant Recipients and Associated Maternal, Neonatal, and Graft Morbidity During 5 Decades of Clinical Practice

Importance

Rates of cesarean delivery (CD) are increased among transplant recipients. There is a need to define the indications for CD and associated outcomes among transplant recipients to determine the safest mode of obstetric delivery.

Objective

To evaluate the association of mode of obstetrical delivery with maternal and neonatal morbidity among pregnant women who have received a kidney or liver transplant.

Design, Setting, and Participants

This registry-based retrospective cohort study used data from the Transplant Pregnancy Registry International, which has recruited participants since 1991 from 289 diverse academic and community settings, mainly in North America. Eligible participants were recipients of a kidney or liver transplant who were aged 18 years or older at the time of a live birth at or later than 20 weeks' gestational age and who delivered between 1968 and 2019. The data were analyzed from April 30, 2020, to April 16, 2021.

Exposures

Scheduled CD, a trial of labor resulting in CD (TOL-CD), or a TOL resulting in vaginal delivery (TOL-VD).

Main Outcomes and Measures

The primary outcomes were severe maternal morbidity and neonatal composite morbidity. Multivariate regression was conducted to calculate odds ratios (ORs) or β values and 95% CIs with adjustment for differences in maternal comorbidities and gestational age at delivery. Nonmedical indications for CD are those not associated with decreased morbidity or mortality in the obstetric literature.

Results

This study included 1865 women, of whom 1435 were kidney transplant recipients and 430 were liver transplant recipients. The age range of the participants was 18 to 48 years; the median body mass index among the participants was in the normal range, and the median transplant-to-conception interval was more than 2 years. Compared with a scheduled CD, a TOL was not associated with increased severe maternal morbidity among kidney transplant recipients (TOL-CD: adjusted odds ratio [aOR], 1.80 [95% CI, 0.77-4.22]; TOL-VD: aOR, 1.22 [95% CI, 0.57-2.62]) (for liver transplant recipients, the numbers were too small for multivariate modeling). In the adjusted model, a TOL was associated with a decrease in neonatal composite morbidity among kidney transplant recipients who underwent TOL-CD (aOR, 0.52; 95% CI, 0.32-0.82) and TOL-VD (aOR, 0.36; 95% CI, 0.24-0.53) and liver transplant recipients who underwent TOL-VD (aOR, 0.41; 95% CI, 0.19-0.87) but not for TOL-CD (aOR, 0.58; 95% CI, 0.21-1.61). The main factors associated with CD after labor were placental abruption (aOR, 12.96; 95% CI, 2.85-59.07) and pregestational diabetes (aOR 5.44; 95% CI, 2.54-11.68). The rate of CD was 51.6% (741 of 1435) among kidney transplant recipients and 41.4% (178 of 430) among liver transplant recipients. In total, 229 of 459 kidney transplant recipients (49.9%) and 50 of 105 liver transplant recipients (47.6%) had scheduled CDs performed for either a nonmedical indication or a repeated indication, although women with these indications are candidates for a TOL.

Conclusions and Relevance

In this cohort study, TOL vs a scheduled CD was associated with improved neonatal outcomes among kidney and transplant recipients and not with increased severe maternal morbidity among kidney transplant recipients. These findings may be used to facilitate multidisciplinary decisions regarding the mode of obstetrical delivery.

Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides an easy access for evaluation of pancreatic allograft dysfunction: six-year experience at a single center

BACKGROUND

The aim of this study is to report our six-year experience with portal-endocrine and gastric-exocrine drainage technique of pancreatic transplantation, which was first developed and implemented at our center in 2007.

METHODS

In this study, the outcomes of all patients at our center who had pancreas transplantation with portal-endocrine and gastric-exocrine drainage technique were evaluated.

RESULTS

From October 2007 to November 2013, 38 patients had pancreas transplantation with this technique - 31 simultaneous kidney pancreas and seven pancreas alone. Median duration of follow-up was 3.8 years. One-, three-, and five-year patient and graft survival rates were 94%, 87%, 70% and 83%, 65%, 49%, respectively. For pancreas allograft dysfunction evaluation, 51 upper endoscopies were performed in 14 patients; donor duodenal biopsies were successfully obtained in 45 (88%). We detected nine episodes of acute rejection (eight patients) and seven episodes of cytomegalovirus (CMV) duodenitis (six patients). No patient developed any complication due to upper endoscopy.

CONCLUSIONS

Portal-endocrine and gastric-exocrine drainage technique of pancreas transplantation provides lifelong easy access to the transplanted duodenum for evaluation of pancreatic allograft dysfunction.

Prednisolone as preservation additive prevents from ischemia reperfusion injury in a rat model of orthotopic lung transplantation

The lung is, more than other solid organs, susceptible for ischemia reperfusion injury after orthotopic transplantation. Corticosteroids are known to potently suppress pro-inflammatory processes when given in the post-operative setting or during rejection episodes. Whereas their use has been approved for these clinical indications, there is no study investigating its potential as a preservation additive in preventing vascular damage already in the phase of ischemia. To investigate these effects we performed orthotopic lung transplantations (LTX) in the rat. Prednisolone was either added to the perfusion solution for lung preservation or omitted and rats were followed for 48 hours after LTX. Prednisolone preconditioning significantly increased survival and diminished reperfusion edema. Hypoxia induced vasoactive cytokines such as VEGF were reduced. Markers of leukocyte invasiveness like matrix metalloprotease (MMP)-2, or common pro-inflammatory molecules like the CXCR4 receptor or the chemokine (C-C motif) ligand (CCL)-2 were downregulated by prednisolone. Neutrophil recruitment to the grafts was only increased in Perfadex treated lungs. Together with this, prednisolone treated animals displayed significantly reduced lung protein levels of neutrophil chemoattractants like CINC-1, CINC-2α/β and LIX and upregulated tissue inhibitor of matrix metalloproteinase (TIMP)-1. Interestingly, lung macrophage invasion was increased in both, Perfadex and prednisolone treated grafts, as measured by MMP-12 or RM4. Markers of anti-inflammatory macrophage transdifferentiation like MRC-1, IL-13, IL-4 and CD163, significantly correlated with prednisolone treatment. These observations lead to the conclusion that prednisolone as an additive to the perfusion solution protects from hypoxia triggered danger signals already in the phase of ischemia and thus reduces graft edema in the phase of reperfusion. Additionally, prednisolone preconditioning might also lead to macrophage polarization as a beneficial long-term effect.

Long-term graft function in a randomized clinical trial comparing laparoscopic versus open donor nephrectomy

OBJECTIVES

To evaluate and compare the long-term graft and survival rates in kidney transplant recipients who had undergone laparoscopic donor nephrectomy versus those who underwent open donor nephrectomy.

MATERIALS AND METHODS

Our study was done with 100 cases of laparoscopic donor nephrectomy and 100 cases of open donor nephrectomy, performed between July 2001 and September 2003. Mean follow-up of recipients in this study was 6.6 ± 2.4 years (range, 1-9.3 y). This study has a longer follow-up than previous randomized clinical trials. We compared patient and graft survival in recipients of laparoscopic donor nephrectomy versus those who had open donor nephrectomy.

RESULTS

Mean duration of kidney warm ischemia time was 8.7 ± 2.7 minutes for laparoscopic donor nephrectomy and 1.8 ± 0.92 minutes for open donor nephrectomy. There were no significant differences in 5-year graft survival between the laparoscopic donor nephrectomy and open donor nephrectomy groups (89.5% vs 84.3%; P = .96). There were no differences in delayed graft function between the laparoscopic donor nephrectomy and open donor nephrectomy groups (8 and 11 patients; P = .135). There was a significant difference in 5-year graft survival between recipients with a history of delayed graft function and those without delayed graft function (63.2% vs 89.7%; P = .04). Despite a longer warm ischemia time in laparoscopic donor nephrectomy group (8.69 vs 1.87 min; P = .0001), warm ischemia time had no effect on graft outcome in long-term follow-up.

CONCLUSIONS

Although earlier experiences with laparoscopic donor nephrectomies were associated with concerns about long-term effects of laparoscopic donation on the graft function in the recipient, our long-term results confirm that laparoscopic donor nephrectomy provides similar graft outcome to open donor nephrectomy.

Evaluation of the updated definition of early allograft dysfunction in donation after brain death and donation after cardiac death liver allografts

BACKGROUND

An updated definition of early allograft dysfunction (EAD) was recently validated in a multicenter study of 300 deceased donor liver transplant recipients. This analysis did not differentiate between donation after brain death (DBD) and donation after cardiac death (DCD) allograft recipients.

METHODS

We reviewed our prospectively entered database for all DBD (n=377) and DCD (n=38) liver transplantations between January 1, 2006 and October 30, 2011. The incidence of EAD as well as its ability to predict graft failure and survival was compared between DBD and DCD groups.

RESULTS

EAD was a valid predictor of both graft and patient survival at six months in DBD allograft recipients, but in DCD allograft recipients there was no significant difference in the rate of graft failure in those with EAD (11.5%) compared with those without EAD (16.7%) (P=0.664) or in the rate of death in recipients with EAD (3.8%) compared with those without EAD (8.3%) (P=0.565). The graft failure rate in the first 6 months in those with international normalized ratio ≥1.6 on day 7 who received a DCD allograft was 37.5% compared with 6.7% for those with international normalized ratio <1.6 on day 7 (P=0.022).

CONCLUSIONS

The recently validated definition of EAD is a valid predictor of patient and graft survival in recipients of DBD allografts. On initial assessment, it does not appear to be a useful predictor of patient and graft survival in recipients of DCD allografts, however a study with a larger sample size of DCD allografts is needed to confirm these findings. The high ALT/AST levels in most recipients of DCD livers as well as the predisposition to biliary complications and early cholestasis make these parameters as poor predictors of graft failure. An alternative definition of EAD that gives greater weight to the INR on day 7 may be more relevant in this population.

Influence of erythropoietin on arterial stiffness and endothelial function in renal transplant recipients

BACKGROUND/AIMS

Recent retrospective studies suggest an association of therapy with erythropoiesis-stimulating agents (ESAs) and increased mortality in renal transplant recipients (RTR). Large artery structure and function are significantly impaired in RTR which contributes to their high cardiovascular morbidity and could be altered by erythropoietin. We aimed to examine the influence of ESA therapy on large artery stiffness and endothelial function in RTR.

METHODS

63 RTR with chronic allograft dysfunction and renal anemia were randomized to a group receiving darbepoetin alfa (Dar) and a control group (Co). At baseline and after 8 months of treatment (cumulative Dar dose 11.1 µg/kg b.w.) brachial and common carotid artery distensibility coefficients, aortic pulse wave velocity, brachial artery flow-mediated and nitroglycerin-mediated vasodilation were measured as well as the following biomarkers of vascular function: vWF, sVCAM, sICAM, E-selectin, t-PA and PAI-1.

RESULTS

23 patients in the Dar group and 17 patients in the Co group were available for per-protocol analysis. Hemoglobin increased significantly from 10.9 to 12.6 g/dl after 8 months in the Dar group, whereas it remained stable at 11.3 g/dl in the Co group. Effects on large artery stiffness, endothelial function and biomarkers of vascular function did not differ significantly between the two groups.

CONCLUSION

Therapy with Dar during 8 months did not significantly impact parameters of large artery stiffness and endothelial function in RTR. These data suggest that therapy with erythropoietin does not deteriorate arterial stiffness and endothelial function in RTR.

Five-year outcomes after a change from a cyclosporin-based to a 'low-dose' tacrolimus-based primary immunosuppression regimen for incident kidney transplants--the Glasgow experience

In January 2007, our centre changed from a cyclosporin (CyA)/azathioprine (Aza)/ prednisolone (Pred) primary immunosuppression regimen (with basiliximab induction and mycophenolate mofetil [MMF] for those at immunologically high risk) to a tacrolimus (Tac) (low dose)/MMF/Pred regimen with basiliximab induction, following presentation of Symphony trial results. This analysis assesses the impact of this change on 5-year outcomes. Three hundred consecutive renal-only transplants were identified: 140 from the 2005-06 era and 160 from the 2007-08 era. The proportions of living donor (37.5 vs. 22.9%; p = 0.04) and donors after circulatory death (11.9 vs. 5.0%; p = 0.03) were higher in the 2007-08 cohort. Five-year actuarial patient survival was higher in the 2007-08 cohort (96.8 vs. 87.1%; p = 0.003), with a trend toward higher 5-year transplant survival (84.7 vs. 76.3%; p = 0.08). Estimated glomerular filtration rate (eGFR) was higher than in the 2005-06 era at 1 (53.5 vs. 44.5 ml/min/1.73m2; p = 0.0006) and 3 years (50.9 vs. 43.4 ml/min/1.73m2; p = 0.02), with a trend toward higher eGFR at 5 years (41.8 vs. 49.6 ml/min/1.73m2; p = 0.09). Differences were consistent when living donor and deceased donor transplants were analysed separately. In a "real world" population, a change from a CyA-based to a Tac (low-dose)/MMF/Pred primary immunosuppression regimen has been associated with better 5-year outcomes.

[Albumin dialysis (MARS therapy) in patients with hepatic graft dysfunction]

A primary nonfunctioning graft, the complication that develops in less than 5% of patients within the first 24-48 hours after hepatic transplantation, is responsible for high death rates in recipients. Its manifestations are an extremely grave clinical condition, hypotension, unconsciousness, progressive signs of hepatocytic insufficiency with increases in bilirubin levels and serum transaminase activities, addition of renal failure, and development of multiple organ dysfunctions. Eight patients underwent a total of 17 albumin dialysis sessions (1 to 5; mean 2.1). Each session lasted 6 hours. Albumin dialysis caused a significant reduction in the levels of serum bilirubin and its conjugated fraction, by an average of 24.7 +/- 15.1% per session. The activity of the serum enzymes of cytolysis and cholestasis significantly decreased with the parameters being stabilized within 7 days. Stabilization of hemodynamic parameters and better neurological status were noted in patients during treatment. The survival rate was 75% on days 7, 20, and 30. Hepatic retransplantation was made in 2 patients; 4 were discharged home and 2 died from multiple organ dysfunctions. Albumin dialysis used in patients with graft dysfunction provides a possibility of maintaining the patient in the critical period of searching for a donor's organ or regenerating the graft's function.