Pediatric Acute Liver Failure Due to Type 2 Autoimmune Hepatitis Associated With SARS-CoV-2 Infection: A Case Report.

Although elevated liver enzymes are common in hospitalized children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, pediatric acute liver failure is an uncommon manifestation of COVID-19 disease. We describe the case of a 3-year-old previously healthy female who developed acute liver failure secondary to type 2 autoimmune hepatitis preceded by mild infection with SARS-CoV-2. Testing for viral hepatitis was negative, and the patient did not meet diagnostic criteria for multisystem inflammatory disease in children (MIS-C). A liver biopsy showed acute submassive hepatocyte necrosis with brisk CD3+ T lymphocyte infiltration and no evidence of fibrosis or chronic liver disease. Treatment with high-dose methylprednisolone resulted in rapid normalization of alanine aminotransferase (ALT), aspartate aminotransferase (AST), international normalized ratio (INR), and ammonia levels, and liver transplantation was avoided. This case highlights a possible association between SARS-CoV-2 infection and subsequent development of autoimmune liver disease presenting with acute liver failure.

Serum Proteomics Uncovers Biomarkers of Clinical Portal Hypertension in Children With Biliary Atresia.

Children with biliary atresia (BA) often develop portal hypertension (PHT) and its complications, which are associated with high morbidity and mortality. The goal of this study was to identify serum biomarkers of PHT by using large-scale proteomics. We applied the slow off-rate modified aptamer scan (SOMAscan) to measure 1,305 proteins in serum samples of children with BA with and without clinical evidence of PHT in validation and discovery cohorts enrolled in the Biliary Atresia Study of Infants and Children. Serum proteomics data was analyzed using logistic regression to identify protein(s) with an area under the receiver operating characteristic curve (AUROC) ≥ 0.90. Immunostaining was used to characterize the cellular localization of the new biomarker proteins in liver tissues. We identified nine proteins in the discovery cohort (n = 40 subjects) and five proteins in the validation cohort (n = 80 subjects) that individually or in combination predicted clinical PHT with AUROCs ≥ 0.90. Merging the two cohorts, we found that semaphorin 6B (SEMA6B) alone and three other protein combinations (SEMA6B+secreted frizzle protein 3 [SFRP3], SEMA6B+COMM domain containing 7 [COMMD7], and vascular cell adhesion molecule 1 [VCAM1]+BMX nonreceptor tyrosine kinase [BMX]) had AUROCs ≥ 0.90 in both cohorts, with high positive- and negative-predictive values. Immunostaining of the new protein biomarkers showed increased expression in hepatic endothelial cells, cholangiocytes, and immune cells within portal triads in BA livers with clinical PHT compared to healthy livers. Conclusion: Large-scale proteomics identified SEMA6B, SFRP3, COMMD7, BMX, and VCAM1 as biomarkers highly associated with clinical PHT in BA. The expression of the biomarkers in hepatic epithelial, endothelial, and immune cells support their potential role in the pathophysiology of PHT.

Operational tolerance after pediatric composite liver-pancreas-intestine transplantation following severe graft-versus-host disease.

BACKGROUND: While operational tolerance has been previously described in isolated intestinal transplant, reports of this phenomenon in combined liver-intestine transplant are lacking. CASE DESCRIPTION: We detail a unique case of a patient who received a composite allograft including liver, pancreas, and small bowel due to short gut syndrome secondary to gastroschisis complicated by volvulus. The indication for transplantation was permanent dependence on total parenteral nutrition, end-stage liver disease, recurrent sepsis, and persistent stomal variceal hemorrhage. The patient developed severe graft-versus-host disease with grade 3 skin involvement, ophthalmic, and pulmonary involvement with 53% donor T-cell chimerism. She required aggressive therapy including high-dose methylprednisolone, rituximab, cyclophosphamide, and alemtuzumab. Due to infection concerns following depletion of her lymphocytes, immunosuppression was discontinued with close surveillance of her allograft. Nearly 10 years later, the patient has continued off all immunosuppression without evidence of rejection or graft dysfunction and demonstrates immunocompetence with normal functional immune assays and development of appropriate live vaccination titers. CONCLUSION: This report of operational tolerance following pediatric composite liver-pancreas-intestine transplantation provides evidence that the complex immunologic balance in intestinal transplantation may on rare occasions favor immunosuppression reduction or even discontinuation. Future trials of immunosuppression minimization in this population may be warranted.