Blood PGLYRP1 mRNA shows promise as early marker of ARDS in sepsis

A new retrospective cohort study, published in BMC Pulmonary Medicine, reports that messenger RNA levels of peptidoglycan recognition protein 1 (PGLYRP1) in peripheral blood leukocytes, measured within two hours of ICU admission, were strongly associated with subsequent ARDS during the ICU stay.

The single-center study included 202 adults with sepsis who had no ARDS at the time of admission sampling. The researchers measured PGLYRP1 mRNA expression by reverse-transcription quantitative PCR in blood leukocytes collected within two hours of ICU admission. During the ICU stay, 86 patients developed ARDS. Median PGLYRP1 expression was 18.91 (interquartile range 12.16–32.16) in patients who developed ARDS, compared with 10.57 (7.63–15.24) in those who did not, a difference that was statistically significant (P < 0.001).

In multivariable logistic regression adjusting for age, sex, pulmonary infection, septic shock and admission Sequential Organ Failure Assessment (SOFA) score, each doubling of PGLYRP1 expression was associated with higher odds of subsequent ARDS, with an adjusted odds ratio of 3.572 (95% confidence interval 2.179–5.854; P < 0.001). The authors note that neutrophil-related host responses are prominent in sepsis-associated ARDS, which motivated examining this leukocyte-derived transcript as a candidate marker.

The team also assessed predictive performance. The apparent area under the receiver operating characteristic curve was 0.792 for PGLYRP1 alone, 0.719 for a clinical model built from admission variables, and 0.818 for a combined model. Adding PGLYRP1 to the clinical model improved apparent discrimination significantly (ΔAUC = 0.0989; P < 0.001), but the combined model did not significantly outperform PGLYRP1 alone (ΔAUC = 0.0265; P = 0.122). Calibration, Brier scores and decision curves were evaluated alongside discrimination, and internal validation using 1000 bootstrap resamples and 10-fold cross-validation repeated ten times yielded an optimism-corrected AUC of 0.797 and a mean cross-validated AUC of 0.790 for the combined model.

The authors describe these as exploratory findings. Because the study was single-center and retrospective, and the biomarker was measured at a single early time point, the association does not establish that PGLYRP1 plays a causal role in ARDS development, nor does it demonstrate that measuring the marker would change patient outcomes. The paper concludes that prospective multicenter validation and evaluation of clinical impact are needed before any use at the bedside.

Subject of Research: PGLYRP1 mRNA in blood leukocytes as a candidate early marker of ARDS in sepsis

Article Title: Peripheral blood leukocyte PGLYRP1 mRNA as a candidate marker of subsequent acute respiratory distress syndrome in sepsis: a retrospective cohort study

Article References: Qian, Y., Zou, L., Pan, Y., Xu, Q., & Lu, W. (2026). Peripheral blood leukocyte PGLYRP1 mRNA as a candidate marker of subsequent acute respiratory distress syndrome in sepsis: a retrospective cohort study. BMC Pulmonary Medicine. https://doi.org/10.1186/s12890-026-04907-7

Image Credits: AI Generated

DOI: 10.1186/s12890-026-04907-7

Keywords: sepsis, ARDS, PGLYRP1, biomarker, mRNA, intensive care, retrospective cohort, logistic regression, SOFA score, neutrophils, Peripheral, blood