Early Bedside Biomolecular Phenotyping and Precision Medicine in Lung Transplant Recipients

BackgroundLung transplantation (LUTX) is frequently complicated by Primary Graft Dysfunction (PGD), a heterogeneous form of acute lung injury associated with multi-organ failure and rejection. We hypothesized that early, bedside plasma biomarkers could capture this biological heterogeneity, identifying phenotypes with differential clinical outcomes. MethodsThis two-year prospective single-center observational study enrolled 78 bilateral LUTX recipients. With a real-time point-of-care immunoanalyzer we measured IL-1{beta}, IL-2, IL-6, IFN-{gamma}, TNF, CCL-2, IL-15, Ferritin, and D-dimer 36 hours post-reperfusion. Outcome-agnostic Latent Profile Analysis (LPA) was applied to identify bio-signatures. PGD (grade 3) incidence and clinical outcomes were compared across classes. ResultsLPA identified three distinct classes, interpreted as biological sub-phenotypes. The Adaptive phenotype (68%) had the lowest inflammatory activation, shortest vasoactive support and Invasive Mechanical Ventilation (IMV) (both 1 day) and ICU stay (3 days), and lowest 72-hours PGD (8%) and Acute Kidney Injury (AKI) (28%) rates. The Hyperinflammatory phenotype (18%) showed the highest IL-6 and Ferritin levels with resolving PGD (69% to 23%, from 6 to 72 hours), but prolonged IMV (6 days), vasoactive support (3 days), ICU stay (7 days), with a high AKI rate (69%). The Coagulopathic phenotype (15%), requiring more intraoperative blood products, exhibited the highest TNF and D-dimer with persistent PGD (36% at 24 and 72 hours), intermediate vasoactive support (2 days), and AKI severity. Six-month rejection-free survival was similar across phenotypes. ConclusionsThis preliminary hypothesis-generating study suggests that point-of-care biomarkers after LUTX may identify biological phenotypes with potential clinical relevance. Future studies are needed to confirm such phenotyping.