American journal of respiratory and critical care medicine
-
Am. J. Respir. Crit. Care Med. · Dec 2022
The Lung Allograft Microbiome Associates with Pepsin, Inflammation, and Primary Graft Dysfunction.
Rationale: Primary graft dysfunction (PGD) is the principal cause of early morbidity and mortality after lung transplantation. The lung microbiome has been implicated in later transplantation outcomes but has not been investigated in PGD. Objectives: To define the peritransplant bacterial lung microbiome and relationship to host response and PGD. ⋯ Together, immediate postimplantation allograft Prevotella/Streptococcus ratio, pepsin, and indicator cytokines were associated with development of severe PGD during the 72-hour post-transplantation period (area under the curve = 0.81). Conclusions: Lung allografts that develop PGD have a microbiome enriched in anaerobic oropharyngeal taxa, elevated gastric pepsin, and hyperinflammatory phenotype. These findings suggest a possible role for peritransplant aspiration in PGD, a potentially actionable mechanism that warrants further investigation.