A blood-based PT-LIFE (Pediatric Liver Transplantation-LIver Fibrosis Evaluation) biomarker panel for non-invasive evaluation of pediatric liver fibrosis after liver transplantation: a prospective derivation and validation study.

Allograft fibrosis is increasingly detected in graft biopsies as the postoperative period extends, potentially emerging as a pivotal determinant of long-term graft function and graft survival among pediatric recipients. Currently, there is a paucity of non-invasive diagnostic tools capable of identifying allograft fibrosis in pediatric recipients of liver transplants. This study involved 507 pediatric liver transplant patients and developed a novel blood-based diagnostic assay, PT-LIFE, to noninvasively distinguish allograft fibrosis using blood samples, clinical data, and biopsy outcomes. The PT-LIFE assay was derived from a matrix of 23 variables and validated in two independent cohorts. It integrates three biomarkers (LECT2, YKL-40, FBLN3) with an AUROC of 0.91. In the pooled analysis, a PT-LIFE score lower than 0.12 identified LAFSc 0-2 with a sensitivity of 91.9%, whereas scores above 0.29 indicated LAFSc 3-6, with a specificity of 88.4%. The PT-LIFE assay presents as a promising non-invasive diagnostic tool for the detection of allograft fibrosis in pediatric liver transplant recipients. The study is registered with ClinicalTrials.gov, identifier NCT05308628.