Genetic landscape of pediatric acute liver failure of indeterminate origin.

BACKGROUND AIMS Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, main causes are viral infections (12-16%) and inherited metabolic diseases (14-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. METHODS With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. RESULTS In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF (RALF). WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (46%), and in children with RALF (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8) and DGUOK (n=7) were the most frequent findings. When categorizing, most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%) and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplants. CONCLUSION This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics

The role of everolimus in liver transplantation

Rainer Ganschow,1 Jörg-Matthias Pollok,2 Martin Jankofsky,3 Guido Junge4 1Department of Pediatrics, 2Department of General, Visceral, Thoracic, and Vascular Surgery, 3Department of Pediatrics, University of Bonn, Bonn, Germany; 4Integrated Hospital Care, Novartis Pharma AG, Basel, SwitzerlandAbstract: During the last 5 decades, liver transplantation has witnessed rapid development in terms of both technical and pharmacologic advances. Since their discovery, calcineurin inhibitors (CNIs) have remained the standard of care for immunosuppression therapy in liver transplantation, improving both patient and graft survival. However, adverse events, particularly posttransplant nephrotoxicity, associated with long-term CNI use have necessitated the development of alternate treatment approaches. These include combination therapy with a CNI and the inosine monophosphate dehydrogenase inhibitor mycophenolic acid and use of mammalian target of rapamycin (mTOR) inhibitors. Everolimus, a 40-O-(2-hydroxyethyl) derivative of mTOR inhibitor sirolimus, has a distinct pharmacokinetic profile. Several studies have assessed the role of everolimus in liver transplant recipients in combination with CNI reduction or as a CNI withdrawal strategy. The efficacy of everolimus-based immunosuppressive therapy has been demonstrated in both de novo and maintenance liver transplant recipients. A pivotal study in 719 de novo liver transplant recipients formed the basis of the recent approval of everolimus in combination with steroids and reduced-dose tacrolimus in liver transplantation. In this study, everolimus introduced at 30 days posttransplantation in combination with reduced-dose tacrolimus (exposure reduced by 39%) showed comparable efficacy (composite efficacy failure rate of treated biopsy-proven acute rejection, graft loss, or death) and achieved superior renal function as early as month 1 and maintained it over 2 years versus standard exposure tacrolimus. This review provides an overview of the efficacy and safety of everolimus-based regimens in liver transplantation in the de novo and maintenance settings, as well as in special populations such as patients with hepatocellular carcinoma recurrence, hepatitis C virus-positive patients, and pediatric transplant recipients. We also provide an overview of ongoing studies and discuss potential expansion of the role for everolimus in these settings.Keywords: mTOR inhibitors, everolimus, liver transplantation, efficacy, safety&nbsp

Effects of bioaerosol polluted outdoor air on airways of residents: a cross sectional study

Background: Bioaerosol pollution of workplace and home environments mainly affects airways and mucous membranes. The effect of environmental outdoor residential bioaerosol pollution, for example, livestock holdings, farming, and waste disposal plants, is unclear. Aims: To investigate the perceived health of residents living in areas with measurable outdoor bioaerosol pollution (for example, spores of Aspergillus fumigatus and actinomycetes), and effects of accompanying odours. Methods: In a cross sectional study, double blinded to ongoing microbial measurements, doctors collected 356 questionnaires from residents near a large scale composting site, and from unexposed controls in 1997. Self reported prevalence of health complaints during the past year, doctors' diagnoses, as well as residential odour annoyance were assessed. Microbiological pollution was measured simultaneously in residential outdoor air. Results: Concentrations of >10(5) colony forming units of thermophilic actinomycetes, moulds, and total bacteria/m(3) air were measured 200 m from the site, dropping to near background concentrations within 300 m. Positive adjusted associations were observed for residency within 150–200 m from the site versus unexposed controls for self reported health complaints: "waking up due to coughing", odds ratio (OR) 6.59 (95% confidence interval (CI) 2.57 to 17.73); "coughing on rising or during the day", OR 3.18 (95% CI 1.24 to 8.36); "bronchitis", OR 3.59 (95% CI 1.40 to 9.4); and "excessive tiredness", OR 4.27 (95% CI 1.56 to 12.15). Reports of irritative airway complaints were associated with residency in the highest bioaerosol exposure, 150–200 m (versus residency >400–500 m) from the site, and period of residency more than five years, but not residential odour annoyance. Lifetime prevalence of self reported diseases did not differ with exposure. Conclusions: Bioaerosol pollution of residential outdoor air can occur in concentrations found in occupational environments. For the first time residents exposed to bioaerosol pollution were shown to report irritative respiratory complaints similar to mucous membrane irritation independently of perceived odours

Genetic landscape of pediatric acute liver failure of indeterminate origin

\ua9 2024 Lippincott Williams and Wilkins. All rights reserved.Background and Aims: Pediatric acute liver failure (PALF) is a life-threatening condition. In Europe, the main causes are viral infections (12%-16%) and inherited metabolic diseases (14%-28%). Yet, in up to 50% of cases the underlying etiology remains elusive, challenging clinical management, including liver transplantation. We systematically studied indeterminate PALF cases referred for genetic evaluation by whole-exome sequencing (WES), and analyzed phenotypic and biochemical markers, and the diagnostic yield of WES in this condition. Approach and Results: With this international, multicenter observational study, patients (0-18 y) with indeterminate PALF were analyzed by WES. Data on the clinical and biochemical phenotype were retrieved and systematically analyzed. Results: In total, 260 indeterminate PALF patients from 19 countries were recruited between 2011 and 2022, of whom 59 had recurrent PALF. WES established a genetic diagnosis in 37% of cases (97/260). Diagnostic yield was highest in children with PALF in the first year of life (41%), and in children with recurrent acute liver failure (64%). Thirty-six distinct disease genes were identified. Defects in NBAS (n=20), MPV17 (n=8), and DGUOK (n=7) were the most frequent findings. When categorizing, the most frequent were mitochondrial diseases (45%), disorders of vesicular trafficking (28%), and cytosolic aminoacyl-tRNA synthetase deficiencies (10%). One-third of patients had a fatal outcome. Fifty-six patients received liver transplantation. Conclusions: This study elucidates a large contribution of genetic causes in PALF of indeterminate origin with an increasing spectrum of disease entities. The high proportion of diagnosed cases and potential treatment implications argue for exome or in future rapid genome sequencing in PALF diagnostics