Human leukocyte antigen compatibility and incidence of donor-specific antibodies in pediatric liver transplant recipients.

BACKGROUND: Antibody-mediated rejection following liver transplantation (LT) has been increasingly recognized, particularly with respect to the emergence of de novo donor-specific antibodies (DSAs) and their impact on graft longevity. While substantial evidence for adult populations exists, research focusing on pediatric LT outcomes remains limited. AIM: To investigate the prevalence of human leukocyte antigen (HLA) mismatches and DSA and evaluate their association with rejection episodes after pediatric LT. METHODS: A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre, Brazil, between December 2013 and December 2023. Only patients who survived for > 30 days after LT with at least one DSA analysis were included. DSA classes I and II and cross-matches were analyzed. The presence of de novo DSA (dnDSA) was evaluated at least 3 months after LT using the Luminex® single antigen bead method, with a positive reaction threshold set at 1000 MFI. Rejection episodes were confirmed by liver biopsy. RESULTS: Overall, 67 transplanted children were analyzed; 61 received grafts from living donors, 85% of whom were related to recipients. Pre-transplant DSA (class I or II) was detected in 28.3% of patients, and dnDSA was detected in 48.4%. The median time to DSA detection after LT was 19.7 [interquartile range (IQR): 4.3-35.6] months. Biopsy-proven rejection occurred in 13 patients at follow-up, with C4d positivity observed in 5/13 Liver biopsies. The median time to rejection was 7.8 (IQR: 5.7-12.8) months. The presence of dnDSA was significantly associated with rejection (36% vs 3%, P < 0.001). The rejection-free survival rates at 12 and 24 months were 76% vs 100% and 58% vs 95% for patients with dnDSA anti-DQ vs those without, respectively. CONCLUSION: Our findings highlight the importance of incorporating DSA assessment into pre- and post-transplantation protocols for pediatric LT recipients. Future implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recipients.

Incidence, management and outcomes in hepatic artery complications after paediatric liver transplantation: protocol of the retrospective, international, multicentre HEPATIC Registry.

INTRODUCTION: Hepatic artery complications (HACs), such as a thrombosis or stenosis, are serious causes of morbidity and mortality after paediatric liver transplantation (LT). This study will investigate the incidence, current management practices and outcomes in paediatric patients with HAC after LT, including early and late complications. METHODS AND ANALYSIS: The HEPatic Artery stenosis and Thrombosis after liver transplantation In Children (HEPATIC) Registry is an international, retrospective, multicentre, observational study. Any paediatric patient diagnosed with HAC and treated for HAC (at age <18 years) after paediatric LT within a 20-year time period will be included. The primary outcomes are graft and patient survivals. The secondary outcomes are technical success of the intervention, primary and secondary patency after HAC intervention, intraprocedural and postprocedural complications, description of current management practices, and incidence of HAC. ETHICS AND DISSEMINATION: All participating sites will obtain local ethical approval and (waiver of) informed consent following the regulations on the conduct of observational clinical studies. The results will be disseminated through scientific presentations at conferences and through publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: The HEPATIC registry is registered at the ClinicalTrials.gov website; Registry Identifier: NCT05818644.

High prevalence of response to PPI treatment in children and adolescents with eosinophilic esophagitis in southern Brazil.

Introduction: Eosinophilic esophagitis is a newly recognized entity, in which there is significant evidence available that clearly demonstrates the positive impact of PPIs on reducing esophageal eosinophilia in individuals across different age groups, including children, adolescents, and adults. Multiple mechanisms have been proposed to explain how this treatment effect occurs. In Brazil, there seems to be a lack of studies that have prospectively assessed the clinical and therapeutic response rate in pediatric patients with EoE. The objective of this study was to prospectively evaluate the clinical and therapeutic response of pediatric patients with EoE in a medical center located in southern Brazil, by investigating the effectiveness of PPI treatment. Methods: This study is a clinical, prospective, open trial that took place in a pediatric hospital located in southern Brazil. The focus of the study was on patients diagnosed with Eosinophilic Esophagitis (EoE) who were given treatment using omeprazole/esomeprazole at a dosage of 1 mg.kg per dose, twice daily, for a period of 8-12 weeks. Following the treatment period, the patients underwent another endoscopy. Patients who exhibited 15 or less eosinophils in the biopsy conducted after the treatment were considered as responders. Results: A total of 27 patients was evaluated (74.1% boys). The average age (± standard deviation) was 8 years (±4). Nineteen patients (70.3%) were considered as responders to PPI treatment: 6 patients-22.2%-exhibited a complete response (defined as having 5 or fewer eosinophil per high power field. Additionally, 13 patients-48.1%-demonstrated a partial response, characterized by eosinophil counts exceeding 5 but less than 15 eos/hpf. When comparing the responder and non-responder groups at presentation, a statistical difference was observed in the prevalence of food refusal as a presenting symptom. Food refusal was found to be more prevalent in the non-responder group (87.5% vs. 26.3%, P = 0.008). No differences were observed in terms of atopy history and endoscopic scores. Upon comparing the histological findings from the post-treatment endoscopy of the two groups, it was observed that PPI responders exhibited a greater tendency to decrease basal cell hyperplasia (P = 0.06) and intercellular edema (P = 0.08). Conclusion: In this group of pediatric patients with EoE in Southern Brazil most patients showed a high prevalence of histological, endoscopic, and clinical response to PPI treatment. PPIs showed efficacy in Brazilian patients with EoE, most of whom would probably not be able to adequately undergo other treatments. Clinical Trial Registration: https://ensaiosclinicos.gov.br/rg/RBR-2ntbth9, identifier (U1111-1301-1842).

Primary liver transplantation vs transplant after Kasai portoenterostomy in children with biliary atresia: A retrospective Brazilian single-center cohort.

BACKGROUND: Biliary atresia (BA) is the most common indication for pediatric liver trans plantation, although portoenterostomy is usually performed first. However, due to the high failure rate of portoenterostomy, liver transplantation has been advocated as the primary procedure for patients with BA. It is still unclear if a previous portoenterostomy has a negative impact on liver transplantation outcomes. AIM: To investigate the effect of prior portoenterostomy in infants un dergoing liver transplantation for BA. METHODS: This was a retrospective cohort study of 42 pediatric patients with BA who underwent primary liver transplantation from 2013 to 2023 at a single tertiary center in Brazil. Patients with BA were divided into two groups: Those under going primary liver transplantation without portoenterostomy and those undergoing liver transplantation with prior portoenterostomy. Continuous variables were compared using the Student's t-test or the Kruskal-Wallis test, and categorical variables were compared using the χ2 or Fisher's exact test, as appropriate. Multivariable Cox regression analysis was performed to determine risk factors for portal vein thrombosis. Patient and graft survival analyses were conducted with the Kaplan-Meier product-limit estimator, and patient subgroups were compared using the two-sided log-rank test. RESULTS: Forty-two patients were included in the study (25 [60%] girls), 23 undergoing liver transplantation without prior portoenterostomy, and 19 undergoing liver transplantation with prior portoenterostomy. Patients with prior portoenterostomy were older (12 vs 8 months; P = 0.02) at the time of liver transplantation and had lower Pediatric End-Stage Liver Disease scores (13.2 vs 21.4; P = 0.01). The majority of the patients (35/42, 83%) underwent living-donor liver transplantation. The group of patients without prior portoenterostomy appeared to have a higher incidence of portal vein thrombosis (39 vs 11%), but this result did not reach statistical significance. Prior portoenterostomy was not a protective factor against portal vein thrombosis in the multivariable analysis after adjusting for age at liver transplantation, graft-to-recipient weight ratio, and use of vascular grafts. Finally, the groups did not significantly differ in terms of post-transplant survival. CONCLUSION: In our study, prior portoenterostomy did not significantly affect the outcomes of liver transplantation.

Prevalence, management and efficacy of treatment in portal vein obstruction after paediatric liver transplantation: protocol of the retrospective international multicentre PORTAL registry.

INTRODUCTION: Portal vein obstruction (PVO) consists of anastomotic stenosis and thrombosis, which occurs due to a progression of the former. The aim of this large-scale international study is to assess the prevalence, current management practices and efficacy of treatment in patients with PVO. METHODS AND ANALYSIS: The Portal vein Obstruction Revascularisation Therapy After Liver transplantation registry will facilitate an international, retrospective, multicentre, observational study, with 25 centres around the world already actively involved. Paediatric patients (aged <18 years) with a diagnosed PVO between 1 January 2001 and 1 January 2021 after liver transplantation will be eligible for inclusion. The primary endpoints are the prevalence of PVO, primary and secondary patency after PVO intervention and current management practices. Secondary endpoints are patient and graft survival, severe complications of PVO and technical success of revascularisation techniques. ETHICS AND DISSEMINATION: Medical Ethics Review Board of the University Medical Center Groningen has approved the study (METc 2021/072). The results of this study will be disseminated via peer-reviewed publications and scientific presentations at national and international conferences. TRIAL REGISTRATION NUMBER: Netherlands Trial Register (NL9261).

Consumo de álcool e tabaco em escolares da rede pública de Santarém-PA / Consumption of alcohol and tobacco in students of public schools of Santarém-PA

OBJETIVO: Investigar a prevalência de uso na vida e nos últimos 30 dias de álcool e tabaco e sua associação com características de escolares do oitavo ano da rede pública de Santarém-PA em 2010. MATERIAL E MÉTODOS: Estudo transversal com amostra representativa de 689 escolares, sendo os dados coletados em entrevista e analisados com regressão de Cox. RESULTADOS: O uso na vida de tabaco foi de 12,1% e, destes, 36,1% consumiram nos últimos 30 dias. Houve associação entre uso na vida de cigarro e sexo masculino, consumo pelos pais e amigos, e experiência com álcool pelo jovem. O uso na vida de álcool foi de 40,7% e nos últimos 30 dias, 50,7%. Encontrou-se associação entre uso na vida de álcool e uso de tabaco na vida pelo jovem e consumo de álcool pelos pais. CONCLUSÃO: Os resultados apontam relação significativa entre consumo dessas substâncias pelos pais e pelos filhos.(AU)

OBJECTIVE: investigate the prevalence in life and in the last 30 days of alcohol and tobacco use and the association with adolescent students from the eighth grade of the public schools in Santarém-PA, 2010. METHOD: Cross-sectional study, with 689 students. Data were collected using validated questionnaires and analyzed with Cox regression. RESULTS: The tobacco use was 12,1%, of these 36,1% in the last 30 days. There was an association between the lifetime use of cigarettes and the male population, the consumptions by parents and by friends, and the experience with alcohol by the teenagers. The lifetime use of alcohol was 40,7% and in the last 30 days 50,7%. An association was found between the lifetime use of alcohol by the teenagers with the lifetime use of tobacco and the consumption of alcohol by parents. CONCLUSION: It is indicated a significant relationship between the consumption of the parents and the children.(AU)