Acute Cellular Rejection Episodes Research Articles

Incidence of acute cellular and antibody mediated rejection in heart transplantation from a tertiary care center

Abstract Background Heart transplant greatly increases the survival in patients with end stage heart failure. However, cardiologists and cardiothoracic surgeons face difficulty in detecting rejection at times. Post-cardiac transplant surveillance biopsy remains the gold standard for diagnosing rejection and therapeutic intervention. Purpose The objective is to report our experience of monitoring rejection by endomyocardial biopsy (EMB). Methods The index study is an ambispective one where we evaluated all the patients who underwent heart transplant at our center from 1994 to 2021. Results Heart transplant were carried out in 72 patients within a period of 28 years, with majority being done after 2016. The patients mean age was 31.6 years (10-59 years). The commonest indication was dilated cardiomyopathy (67%) followed by ischemic cardiomyopathy (2.5%), congenital heart disease (7%) and other miscellaneous causes (5%). The mean age of donors was 31.8 years (14-55 years). Eight of the 72 patients died without any post cardiac transplant endomyocardial biopsy. The remaining 64 patients underwent cumulatively a total of 271 endomyocardial biopsy procedures. Majority of endomyocaridal biopsies contained three cores (range 1-7). First EMB procedure was performed in 17 (26.6%) patients within first seven days, 35(53.1%) within the second week and 12(20.3%) after 14 days. Histologically rejection was identified in 42 (66%) patients. Thirty-nine (61%) had only acute cellular rejection (ACR), one (1.6%) had only antibody mediated rejection (AMR) and two (3.1%) had mixed ACR and AMR. These 42 patients with rejection had a total of 90 (33.2%) episodes of ACR detected in 271 endomyocardial biopsies. Out of 90 ACR, 44 (48.9%) occurred in less than six months; seventeen (18.9% of 90 ACR) episodes occurred between six and 12 months and 29 (32.2%) after one year. The mean of presentation of first ACR episode was 36 weeks (range 5 days to 3.6 years). There were 172 endomyocardial procedures within one year of transplantation of which 61 (35%) showed rejection. Ninety-nine endomyocardial procedures were performed one year of transplantation of which 29 (29%) showed rejection. Most common grade in both the time period was ACR grade 1R (International Society for Heart and Lung Transplantation (ISHLT) 2004) (72.1% in ≤1 year and 65.5% in >1 year) followed by 2R and 3R. Thirty-eight (90.4%) of 42 patients expired in less than five years since transplantation. Two (4.8%) patients survived between five to ten years post transplantation and two (4.8%) survived more than ten years. The longest cardiac transplant recipient had completed 23 years since cardiac transplant and is alive till date. Conclusions EMB being the gold standard for cardiac allograft rejection, the cardiac pathologists need to be aware of the various grades of rejection including mixed rejection.Acute cellular rejection (ISHLT 2004)

Successful use of therapeutic plasma exchange for the management of acute lung transplant rejection secondary to immune checkpoint inhibitor therapy

The use of immune checkpoint inhibitors (ICIs) in individuals with a history of solid organ transplantation is fraught with the emergence of solid organ transplantation rejection (SOTR). The current recommendations for the management of SOTRs secondary to ICI include the use of high-dose steroids along with the escalation of immunosuppressive therapy. Therapeutic Plasma Exchange (TPE) has been described to be effective in managing various immune-related toxicities, however, the data for using TPE in the setting of acute SOTRs induced by ICIs are limited. Herein, we describe the successful use of TPE in a patient with a history of bilateral lung transplantation who developed an episode of mixed acute cellular and antibody-mediated lung transplant rejection after a single dose of PD-1 inhibitor Pembrolizumab for the treatment of underlying melanoma.

Recurrent treatment of refractory acute cellular rejection with alemtuzumab after lung transplantation

We present an exceptional case of a lung transplant recipient successfully treated by multiple courses of alemtuzumab for refractory acute cellular rejection.The patient experienced multiple episodes of acute cellular rejection following the transplantation procedure. Alemtuzumab was initiated as third-line rejection treatment and was repeated six times. Each treatment course resulted in complete recovery of the pulmonary function and depletion of T- and B-lymphocytes and NK cells. The onset of rejection was consistently preceded by the recovery of NK cells, while T- and B-lymphocytes remained depleted. This suggests a rejection process mediated by NK cells.This case contributes to recent research findings suggesting that NK cells play a significant role in acute cellular rejection in lung transplant recipients and stresses the importance to further investigate the role of NK cells in rejection. Furthermore, it demonstrates that acute cellular rejection following lung transplantation can be repeatedly managed by treatment with alemtuzumab. Data availability statementThe authors confirm that the data supporting the findings of this study are available within the article.

Study of Risk Factors Associated With Recurrent Primary Sclerosing Cholangitis After Liver Transplantation in Shiraz >From 2011 to 2021.

Primary sclerosing cholangitis is an autoimmune illness affecting the intrahepatic and/or extrahepatic bile ducts that has a varying clinical history and no clear therapy. Recurrence of primary sclerosing cholangitis after transplantation can cause recurring liver failure, decreased survival, and the necessity for retransplant. Here, we explored the incidence of recurrence while also identifying the risk factors of primary sclerosing cholangitis. In this retrospective cohort study, we collected demographic and clinical data from patients with a history of primary sclerosing cholangitis after liver transplant between 2011 and 2021. With SPSS software, we compared results in 2 groups of patients (with and without recurrent sclerosing biliary cholangitis) in terms of demographic and clinical variables. The study included 408 patients. Lower donor age and the occurrence of acute cellularrejection were shown to be key risk factors for recurrence of primary sclerosing cholangitis. Acute cellularrejection showed the best likelihood of predicting primary sclerosing cholangitis recurrence. As the number of acute cellular rejection episodes increased, so did the chance of primary sclerosing cholangitis. Death rate of patients with recurrence of primary sclerosing cholangitis was 40.8% (n = 20 patients) compared with 18.9% (n = 68 patients) in those without recurrence (significant at P < .001). The recurrence of primary sclerosing cholangitis had a detrimental effect on survival after liver transplant. Modifiable risk variables have the potentialto affecttherapies on care and prevention of primary sclerosing cholangitis recurrence. Donor age and acute cellular rejection were risk factors for decreased survival and higher primary sclerosing cholangitis recurrence. The use of mycophenolate (Cellcept) increased recurrence, but tacrolimus reduced mortality.

The CD8+ T cell content of transbronchial biopsies from patients with a first episode of clinically stable grade A1 cellular rejection is associated with future chronic lung allograft dysfunction

T cells drive acute cellular rejection (ACR) and its progression to chronic lung allograft dysfunction (CLAD) following lung transplantation. International Society for Heart and Lung Transplantation grade A1 ACR without associated allograft dysfunction is often untreated, yet some patients develop progressive graft dysfunction. T-cell composition of A1 ACR lesions may have prognostic value; therefore, protein-level and epigenetic techniques were applied to transbronchial biopsytissue to determine whether differential T-cell infiltration in recipients experiencing a first episode of stable grade A1 ACR (StA1R) is associated with early CLAD. Sixty-two patients experiencing a first episode of StA1R were divided into those experiencing CLAD within 2 years (n=13) and those remaining CLAD-free for 5or moreyears (n=49). Imaging mass cytometry (IMC) was used to profile the spectrum and distribution of intragraft T cell phenotypes on a subcohort (n=16; 8 early-CLAD and 8 no early-CLAD). Immunofluorescence was used to quantify CD4+, CD8+, and FOXP3+ cells. Separately, CD3+ cells were fluorescently labeled, micro-dissected, and the degree of Treg-specific demethylated region methylation was determined. PhenoGraph unsupervised clustering on IMC revealed 50 unique immune cell subpopulations. Methylation and immunofluorescence analyses demonstrated no significant differences in Tregs between early-CLAD and no early-CLAD groups. Immunofluorescence revealed that patients who developed CLAD within 2 years of lung transplantation showed greater CD8+ T cell infiltration compared to those who remained CLAD-free for 5 or more years. In asymptomatic patients with a first episode of A1 rejection, greater CD8+ T cell content may be indicative of worse long-term outlook.

Basiliximab Induction and Postoperative Steroid-free Immunosuppression With Tacrolimus in Pediatric Liver Transplantation: A Randomized Clinical Trial.

Optimizing the immunosuppressive regimen is essential to improve the long-term outcomes of pediatric liver transplant recipients. We conducted a prospective, randomized, open-label study to compare the safety and efficacy of 2 treatment approaches during pediatric liver transplantation: tacrolimus monotherapy following basiliximab induction (the study group) and a dual regimen of tacrolimus plus steroids (the control group). A total of 150 patients were enrolled, with 75 patients allocated to each group. In both groups, recipients achieved graft and recipient overall survival rates exceeding 93%, with no statistically significant differences between them. However, the study group exhibited a significantly lower incidence of acute cellular rejection (ACR), delayed occurrence of ACR, and an improved ACR-free survival rate at 2 y compared with the control group. Notably, the study group also showed a significant reduction in the incidence of de novo donor-specific antibodies at 3-mo and 2-y posttransplant. Furthermore, 6 mo after the transplant, the study group demonstrated significant improvements in weight-for-age Z score and height-for-age Z score. No notable differences were observed in postoperative complications or the incidence of liver fibrosis between the 2 groups. Basiliximab induction combine with tacrolimus (TAC) monotherapy is a safe and effective immunosuppressive regimen to reduce the episodes of ACR without influencing the development of liver fibrosis and graft and recipient survival rate after pediatric liver transplantation.

Rejection in the setting of combined Heart and Liver Transplantation

IntroductionEach year the number of combined heart-liver transplants (HLT) increases, with two distinct patient populations proceeding down this pathway. The first are patients with congenital heart disease (CHD), most commonly single ventricle patients palliated with Fontan. The second group are those with long standing congestive hepatopathy, amyloidosis, hemochromatosis, or alcohol induced myopathies and liver disease.One argument for HLT has been the low rate of rejection even among sensitized patients, with reported rejection rates ranging from 0% to 31%. Historically, those with CHD have been highly sensitized which in some cases may prevent or at least delay transplantation. As such, a recent consensus statement by Emamaulee et al. suggest that “there may be an immunological benefit to proceed with HLT with significantly fewer acute cellular and humoral rejection episodes”. The aim of this study is to demonstrate that HLT patients remain at risk for rejection and have required treatment for it. ResultsThere were 15 patients who underwent HLT from January 2017 to February 2022. Of the four patients who did not have CHD, none were considered sensitized, and all underwent induction with basiliximab per our institutional protocol. One of these had rejection. Rejection episodes were identified in four of the 11 CHD patients (36%) patients. ConclusionsIn our study of 15 HLT, including 11 CHD patients (73% denied transplant at ≥ 1 center) demonstrated a higher rate of rejection than previously reported. While theoretically, HLT may mitigate the likelihood of rejection, the risk still exists, and patients benefit from close monitoring commensurate with single organ transplant.

CLINICAL OUTCOMES OF INFLAMMATORY BOWEL DISEASE AFTER ORTHOTOPIC HEART TRANSPLANT

Abstract BACKGROUND Limited data are available on outcomes of patients with pre-existing inflammatory bowel disease (IBD) who undergo orthotopic heart transplantation (OHT) or develop de novo IBD post-OHT. We aimed to assess the incidence and disease outcomes of pre-existing and de novo IBD in OHT patients while evaluating the effect of IBD on OHT outcomes. METHODS A retrospective review of records was performed from a tri-site tertiary care system between July 2000 and July 2022. A total of 83 OHT receipients were concomitantly diagnosed with colitis of infectious or inflammatory etiology. Only patients with a diagnosis of IBD were included. Sub-analyses of the outcomes and immunosuppressive regimens of OHT recepients were done relative to those with pre-existing or de novo IBD. RESULTS A total of 8 OHT patients with concomitant IBD were identified. The median patient age (IQR) was 54 (23) with OHT and IBD onset at 50 (21.2) and 32.5 (15.7), respectively. Six patients were diagnosed with ulcerative colitis (UC) and 2 were diagnosed with Crohn’s disease. Five of the patients were female. All patients developed IBD within 11.5 (8) years within OHT. Only 1 patient developed de novo IBD 15 years after the first OHT and 7 years prior to a second OHT. OHT immunosuppressive regimens included a combination of tacrolimus (TAC) and prednisone (n=2), TAC and mycophenolate mofetil (MMF) (n=2), TAC, MMF, and sirolimus (n=2), TAC and sirolimus (n=1), and MMF with sirolimus (n=1). Therapy for pre-existing IBD included maintenance of 5-aminosalicylic (5-ASA) (n=3), escalation to vedolizumab (VD) (n=2), and discontinuation of IBD therapy (5-ASA and azathioprine) (n=3). De novo IBD consistent with UC (15 years post-OHT) was managed with 5-ASA (n=1). Six patients (including de novo IBD case) maintained clinical and endoscopic remission of IBD with no flares post-OHT while 2 patients (1 UC and 1 CD) with active disease flares responded clinically and endoscopically to VD escalation from 5-ASA and azathioprine. Among two UC patients with ileal J-pouch pre-OHT, 1 developed refractory pouchitis requiring diverting ileostomy (while on TAC and prednisone) with no pouchitis in the other (maintained on TAC and MMF). Good graft tolerance limited to mild acute cellular rejection episodes was noted in 6 patients, while multiple or no rejection episodes were noted in the remaining two. None of the patients developed CMV or MMF-induced colitis. One patient died due to progressive functional decline unrelated to graft failure or IBD. DISCUSSION The clinical course and treatment of IBD preceding OHT or de novo (though rare) is not significantly worsened or altered post-OHT. The majority of patients achieve clinical and endoscopic remission while on heart transplant-related immunosuppression. Biologic therapy escalation to VD resulted in clinical remission with no effect on graft tolerance. Table 1 Clinical outcomes of OHT patients with concomitant IBD

Higher Molecular Injury at Diagnosis of Acute Cellular Rejection Increases the Risk of Lung Allograft Failure: A Clinical Trial.

Rationale: The association of acute cellular rejection (ACR) with chronic lung allograft dysfunction (CLAD) in lung transplant recipients has primarily been described before consensus recommendations incorporating restrictive phenotypes. Furthermore, the association of the degree of molecular allograft injury during ACR with CLAD or death remains undefined. Objectives: To investigate the association of ACR with the risk of CLAD or death and to further investigate if this risk depends on the degree of molecular allograft injury. Methods: This multicenter, prospective cohort study included 188 lung transplant recipients. Subjects underwent serial plasma collections for donor-derived cell-free DNA (dd-cfDNA) at prespecified time points and bronchoscopy. Multivariable Cox proportional-hazards analysis was conducted to analyze the association of ACR with subsequent CLAD or death as well as the association of dd-cfDNA during ACR with risk of CLAD or death. Additional outcomes analyses were performed with episodes of ACR categorized as "high risk" (dd-cfDNA ⩾ 1%) and "low risk" (dd-cfDNA < 1%). Measurements and Main Results: In multivariable analysis, ACR was associated with the composite outcome of CLAD or death (hazard ratio [HR], 2.07 [95% confidence interval (CI), 1.05-4.10]; P = 0.036). Elevated dd-cfDNA ⩾ 1% at ACR diagnosis was independently associated with increased risk of CLAD or death (HR, 3.32; 95% CI, 1.31-8.40; P = 0.012). Patients with high-risk ACR were at increased risk of CLAD or death (HR, 3.13; 95% CI, 1.41-6.93; P = 0.005), whereas patients with low-risk status ACR were not. Conclusions: Patients with ACR are at higher risk of CLAD or death, but this may depend on the degree of underlying allograft injury at the molecular level. Clinical trial registered with www.clinicaltrials.gov (NCT02423070).

Outcomes of lung transplantation from donors with hepatitis C viremia with outpatient initiation of antiviral therapy

Transplantation of lungs from donors with active hepatitis C viremia with early initiation of antiviral therapy has been shown to have similar short- and medium-term outcomes compared to transplantation of lungs from non-viremic donors. Consideration of hepatitis C viremic lungs is particularly helpful in patients with anticipated prolonged time on the waiting list. Whether clinical outcomes remain favorable with delay of initiation of antiviral therapy to the outpatient setting or in patients with higher severity of illness is not well understood. Our transplant center considered hepatitis C nucleic acid testing positive (NAT+) donors for all waitlisted lung transplant candidates without chronic liver disease. For those transplanted with hepatitis C NAT+ lungs, we initiated anti-viral therapy in the outpatient setting and continued treatment for 12 weeks. In a retrospective single center study of 15 lung transplant recipients receiving hepatitis C NAT+ lungs and 88 recipients receiving non-viremic lungs, we tested the hypothesis that deferral of antiviral therapy after transplantation of lungs from hepatitis C NAT+ donors to the outpatient setting would result in similar 1 year survival compared to transplantation of lungs from non-viremic donors. Patients receiving hepatitis C NAT+ lungs had similar baseline characteristics, but had longer index hospital lengths of stay (24 vs. 13 days, p=0.021). Patients receiving hepatitis C NAT+ lungs had fewer episodes of acute cellular rejection in the first year. Patients receiving hepatitis C NAT+ lungs had similar one year survival to patients receiving lungs from non-viremic donors, after controlling for age and lung allocation score (p=0.638). In this small single-center study, outpatient initiation of antiviral therapy for donor-derived hepatitis C is associated with acceptable clinical outcomes and can be considered in patients with high severity of illness.

An Immune Atlas of T Cells in Transplant Rejection: Pathways and Therapeutic Opportunities.

Short-term outcomes in allotransplantation are excellent due to technical and pharmacological advances however, improvement in long-term outcomes has been limited. Recurrent episodes of acute cellular rejection, a primarily T cell-mediated response to transplanted tissue, have been implicated in the development of chronic allograft dysfunction and loss. Although it is well established that acute cellular rejection is primarily a CD4+ and CD8+ T cell mediated response, significant heterogeneity exists within these cell compartments. During immune responses, naïve (orthography) (orthography) CD4+ T cells are activated and subsequently differentiate into specific T helper subsets under the influence of the local cytokine milieu. These subsets have distinct phenotypic and functional characteristics, with reported differences in their contribution to rejection responses specifically. Of particular relevance are the regulatory subsets and their potential to promote tolerance of allografts. Unraveling the specific contributions of these cell subsets in the context of transplantation is complex, but may reveal new avenues of therapeutic intervention for the prevention of rejection.

Heart transplantation and human immunodeficiency virus–navigating drug-drug interactions: a case report

BackgroundAntiretroviral therapy (ART) has led to a decline in human immunodeficiency virus (HIV)-related mortality, but comorbidities, including organ dysfunction, are increasingly the focus of care. Heart transplant (HT) is a very effective therapeutic strategy for end-stage heart failure (HF); however, clinicians may be hesitant due to concerns of complex drug-drug interactions (DDIs) between ART and HT immunosuppressive regimens and the potential impact of ART on long-term HT outcomes. In this report, we describe long-term (76-month) follow-up of a patient with HIV-positive status who underwent orthotopic HT with special emphasis on complex drug interactions.Case presentationA 58-year-old man with HIV-1 developed ischemic cardiomyopathy, progressed to end-stage HF and underwent orthotopic HT. To avoid DDIs with planned immunosuppressive therapies, the ART regimen was modified to consist of lamivudine, tenofovir disoproxil fumarate, rilpivirine, and raltegravir. Following HT, the patient’s immunosuppression consisted of tacrolimus and mycophenolate mofetil. He has had normal cardiac function and no opportunistic infections and was subsequently switched to tenofovir alafenamide, emtricitabine, and bictegravir in combination for convenience. Serial HIV-1 RNA blood levels were constantly below the limit of quantification, and his CD4 count remained above 200 cells/mm3 (30–35%). Several DDIs were identified and addressed; however, his long-term post-HT complications included one episode of asymptomatic acute cellular rejection, adenocarcinoma of the prostate, basal cell carcinoma, cardiac allograft vasculopathy, and peripheral neuropathy.ConclusionThe clinical outcome of this case supports the conclusion of previously published reports, summarized here within, demonstrating that HIV-1 positive status should not preclude HT in carefully selected individuals. Both addressing potential DDIs prior to HT and long-term monitoring for routine post-transplant complications and secondary and incidental malignancies are imperative.

Heart transplantation and anti-HLA antibodY: myocardial dysfunction and prognosis - HeartLAy study.

The presence of anti-human leucocyte antigen (HLA) antibodies has been implicated in a higher incidence of complications as well as mortality rate in heart transplantation. The aim of the study was to identify through non-invasive parameters early signs of myocardial dysfunction in the presence of anti-HLA antibodies but without evidence of antibody-mediated rejection (AMR) and its possible prognostic impact. A total of 113 heart-transplanted patients without acute cellular rejection (ACR) and AMR or cardiac allograft vasculopathy (CAV) were prospectively enrolled and divided into two groups ['HLA+' (50 patients) and 'HLA-' (63 patients)], based on the presence of anti-HLA antibodies. Each patient was followed for 2years after the enrolment, recording episodes of AMR, ACR, CAV, and mortality. Clinical characteristics were similar between the two groups. Among laboratory data, N-terminal pro-B-type natriuretic peptide and high-sensitivity cardiac troponin values were significantly higher in the presence of anti-HLA antibodies (P<0.001 and P=0.003, respectively). The echocardiographic parameters that showed a statistically significant difference between the two groups were deceleration time of E wave (DecT E, P<0.001), left ventricular global longitudinal strain (P<0.001), tricuspid annular plane systolic excursion (P=0.011), tricuspid S' wave (P=0.002), and free wall right ventricular longitudinal strain (fwRVLS, P=0.027), whereas left atrial strain did not differ significantly (P=0.408). Univariate analysis showed that anti-HLA antibodies were associated with the development of CAV at both 1 and 2year follow-up [odds ratio (OR) 11.90, 95% confidence interval (CI) 1.43-90.79, P=0.022 and OR 3.37, 95% CI 1.78-9.67, P=0.024, respectively]. Bivariate analysis demonstrated that both fwRVLS and DecT E were predictors of CAV development independently from HLA status. The presence of circulating anti-HLA antibodies is correlated with a mild cardiac dysfunction, even in the absence of AMR, and CAV development. Interestingly, reduced values of DecT E and fwRVLS were predictors of future development of CAV, independently from anti-HLA antibody.

Frailty: A Strong Impact on Lung Transplant Outcomes?

Frailty: A Strong Impact on Lung Transplant Outcomes?

The Association Between Frailty and Chronic Lung Allograft Dysfunction After Lung Transplantation.

After lung transplantation, both frailty and chronic lung allograft dysfunction (CLAD) commonly develop, and when they do, are associated with poorer outcomes. Given their potential shared mechanisms, we sought to explore the temporal relationship between frailty and CLAD onset. In a single center, we prospectively measured frailty by the short physical performance battery (SPPB) repeatedly after transplant. Because of the nature of the relationship between frailty and CLAD is unknown, we tested the association between frailty, modeled as a time-dependent predictor, and CLAD development as well as CLAD development, modeled as a time-dependent predictor, and frailty development. To do so, we used Cox proportional cause-specific hazards and conditional logistic regression models adjusted for age, sex, race, diagnosis, cytomegalovirus serostatus, posttransplant body mass index, and acute cellular rejection episodes as time-dependent covariates. We tested SPPB frailty as a binary (≤9 points) and continuous predictor (12-point scale); as an outcome, we defined frailty as SPPB ≤9. The 231 participants were a mean age of 55.7 y (SD 12.1). After adjusting for covariates, the development of frailty within 3 y after lung transplant was associated with cause-specific CLAD risk (adjusted cause-specific hazard ratio: 1.76; 95% confidence interval [CI], 1.05-2.92 when defining frailty as SPPB ≤9 and adjusted cause-specific hazard ratio: 1.10, 95% CI, 1.03-1.18 per 1-point worsening in SPPB). CLAD onset did not appear to be a risk factor for subsequent frailty (odds ratio, 4.0; 95% CI, 0.4-197.0). Studying the mechanisms underlying frailty and CLAD could provide new insights into the pathobiology of both and potential targets for intervention.

Ineffective esophageal motility is associated with acute rejection after lung transplantation independent of gastroesophageal reflux.

Gastroesophageal reflux is associated with poorer outcomes after lung transplant, likely through recurrent aspiration and allograft injury. Although prior studies have demonstrated a relationship between impedance-pH results and transplant outcomes, the role of esophageal manometry in the assessment of lung transplant patients remains debated, and the impact of esophageal dysmotility on transplant outcomes is unclear. Of particular interest is ineffective esophageal motility (IEM) and its associated impact on esophageal clearance. To assess the relationship between pre-transplant IEM diagnosis and acute rejection after lung transplantation. This was a retrospective cohort study of lung transplant recipients at a tertiary care center between 2007 and 2018. Patients with pre-transplant anti-reflux surgery were excluded. Manometric and reflux diagnoses were recorded from pre-transplant esophageal function testing. Time-to-event analysis using Cox proportional hazards model was applied to evaluate outcome of first episode of acute cellular rejection, defined histologically per International Society of Heart and Lung Transplantation guidelines. Subjects not meeting this endpoint were censored at time of post-transplant anti-reflux surgery, last clinic visit, or death. Fisher's exact test for binary variables and student's t-test for continuous variables were performed to assess for differences between groups. Of 184 subjects (54% men, mean age: 58, follow-up: 443 person-years) met criteria for inclusion. Interstitial pulmonary fibrosis represented the predominant pulmonary diagnosis (41%). During the follow-up period, 60 subjects (33.5%) developed acute rejection. The all-cause mortality was 16.3%. Time-to-event univariate analyses demonstrated significant association between IEM and acute rejection [hazard ratio (HR): 1.984, 95%CI: 1.03-3.30, P = 0.04], confirmed on Kaplan-Meier curve. On multivariable analysis, IEM remained independently associated with acute rejection, even after controlling for potential confounders such as the presence of acid and nonacid reflux (HR: 2.20, 95%CI: 1.18-4.11, P = 0.01). Nonacid reflux was also independently associated with acute rejection on both univariate (HR: 2.16, 95%CI: 1.26-3.72, P = 0.005) and multivariable analyses (HR: 2.10, 95%CI: 1.21-3.64, P = 0.009), adjusting for the presence of IEM. Pre-transplant IEM was associated with acute rejection after transplantation, even after controlling for acid and nonacid reflux. Esophageal motility testing may be considered in lung transplant to predict outcomes.

Evaluation and management of abnormal liver enzymes in the liver transplant recipient: When, why, and what now?

Evaluation and management of abnormal liver enzymes in the liver transplant recipient: When, why, and what now?

Intra-subject variability in oscillometry correlates with acute rejection and CLAD post-lung transplant.

Chronic lung allograft dysfunction (CLAD) is the major cause of death post-lung transplantation, with acute cellular rejection (ACR) being the biggest contributing risk factor. Although patients are routinely monitored with spirometry, FEV1 is stable or improving in most ACR episodes. In contrast, oscillometry is highly sensitive to respiratory mechanics and shown to track graft injury associated with ACR and its improvement following treatment. We hypothesize that intra-subject variability in oscillometry measurements correlates with ACR and risk of CLAD. Of 289 bilateral lung recipients enrolled for oscillometry prior to laboratory-based spirometry between December 2017 and March 2020, 230 had ≥ 3 months and 175 had ≥ 6 months of follow-up. While 37 patients developed CLAD, only 29 had oscillometry at time of CLAD onset and were included for analysis. These 29 CLAD patients were time-matched with 129 CLAD-free recipients. We performed multivariable regression to investigate the associations between variance in spirometry/oscillometry and the A-score, a cumulative index of ACR, as our predictor of primary interest. Conditional logistic regression models were built to investigate associations with CLAD. Multivariable regression showed that the A-score was positively associated with the variance in oscillometry measurements. Conditional logistic regression models revealed that higher variance in the oscillometry metrics of ventilatory inhomogeneity, X5, AX, and R5-19, was independently associated with increased risk of CLAD (p < 0.05); no association was found for variance in %predicted FEV1. Oscillometry tracks graft injury and recovery post-transplant. Monitoring with oscillometry could facilitate earlier identification of graft injury, prompting investigation to identify treatable causes and decrease the risk of CLAD.

Conversion to belatacept after lung transplantation: Report of 10 cases.

Calcineurin inhibitors (CNIs) remain the cornerstone of maintenance immunosuppression (IS) after lung transplantation (LTx), although CNI-related life-threatening toxic effects may occur. Belatacept, a novel immunosuppressant that blocks a T-cell co-stimulation pathway, is a non-nephrotoxic drug indicated as an alternative to CNIs in kidney Tx. In LTx, there are only a few reports of belatacept conversion as a CNI-free or CNI-sparing IS treatment. We reviewed a series of 10 LTx recipients with conversion to a CNI-free belatacept IS regimen within the first year post-LTx (n = 7) or a belatacept/low-dose CNI combination after the first year (n = 3). Use of belatacept was triggered by severe renal failure in 9 patients and under-IS with previous other IS-related toxicities in 1 patient. Mean estimated glomerular filtration rate after starting belatacept significantly improved at 6 months after initiation and at the last-follow-up (p = 0.006, and p = 0.002 respectively). The incidence of recurrent and/or severe acute cellular rejection (ACR) episodes was high in patients with CNI-free belatacept-based IS (n = 4/7). Chronic graft allograft dysfunction developed in 2 of 9 recipients under belatacept IS. Belatacept was stopped in 6 patients because of recurrent/severe ACR (n = 3), recurrent opportunistic infections (n = 1), center modified policy (n = 1), or other cause (n = 1). Early conversion to CNI-free belatacept-based IS improved renal function in this series but was counterbalanced by a high incidence of recurrent ACR, including life-threatening episodes. Other studies are needed to better determine the indications for its use after LTx, possibly with lower immunological risk IS regimens, such as CNI-sparing belatacept.

T-cell infiltrate intensity is associated with delayed response to treatment in late acute cellular rejection in pediatric liver transplant recipients.

Late acute cellular rejection (ACR) is associated with donor-specific antibodies (DSA) development, chronic rejection, and allograft loss. However, accurate predictors of late ACR treatment response are lacking. ACR is primarily T-cell mediated, yet B cells and plasma cells (PC) also infiltrate the portal areas during late ACR. To test the hypothesis that the inflammatory milieu is associated with delayed response (DR) to rejection therapy, we performed a single-center retrospective case-control study of pediatric late liver ACR using multiparameter immunofluorescence for CD4, CD8, CD68, CD20, and CD138 to identify immune cell subpopulations. Pediatric liver transplant recipients transplanted at <17 years of age and treated for biopsy-proven late ACR between January 2014 and 2019 were stratified into rapid response (RR) and DR based on alanine aminotransferase (ALT) normalization within 30 days of diagnosis. All patients received IV methylprednisolone as an initial rejection treatment. Immunofluorescence was performed on archived formalin-fixed paraffin embedded (FFPE) liver biopsy tissue. Liver biopsies from 60 episodes of late ACR in 54 patients were included in the analysis, of which 33 were DR (55%). Anti-thymocyte globulin was only required in the DR group. The frequency of liver-infiltrating CD20+ and CD8+ lymphocytes and the prevalence of autoantibodies were higher in the DR group. In univariate logistic regression analysis, serum gamma-glutamyl transpeptidase (GGT) level at diagnosis, but not ALT, Banff score or presence of DSA, predicted DR. Higher serum GGT level, presence of autoantibodies, and increased CD8+ T-cell infiltration portends DR in late ACR treatment in children.