Multi-omic characterization of pediatric ARDS via nasal brushings.

rationaleWhile nasal brushing transcriptomics can identify disease subtypes in chronic pulmonary diseases, it is unknown whether this is true in pediatric acute respiratory distress syndrome (PARDS).

objectivesDetermine whether nasal transcriptomics and methylomics can identify clinically meaningful PARDS subgroups that reflect important pathobiological processes.

methodsNasal brushings and serum were collected on days 1, 3, 7, and 14 from control and PARDS subjects from two centers. PARDS duration was the primary endpoint. MEASUREMENTS AND MAIN

resultsTwenty-four control and 39 PARDS subjects were enrolled. Two nasal methylation patterns were identified. Compared to Methyl Subgroup 1, Subgroup 2 had hypomethylation of inflammatory genes and was enriched for immunocompromised subjects. Four transcriptomic patterns were identified with temporal patterns indicating injury, repair, and regeneration. Over time, both inflammatory (Subgroup B) and cell injury (Subgroup D) patterns transitioned to repair (Subgroup A) and eventually homeostasis (Subgroup C). When control specimens were included, they were largely Subgroup C. In comparison with 17 serum biomarkers, the nasal transcriptome was more predictive of prolonged PARDS. Subjects with initial Transcriptomic Subgroup B or D assignment had median PARDS duration of 8 days compared to 2 in A or C (p = 0.02). For predicting PARDS duration ≥ 3 days, nasal transcriptomics was more sensitive and serum biomarkers more specific.

conclusionsPARDS nasal transcriptome may reflect distal lung injury, repair, and regeneration. A combined nasal PCR and serum biomarker assay could be useful for predictive and diagnostic enrichment. Trial registration Clinicaltrials.gov NCT03539783 May 29, 2018.