Piezo2 as a novel biomarker of acute respiratory distress syndrome severity: a prospective observational study

Acute respiratory distress syndrome (ARDS) is a life-threatening condition. While mechanical ventilation remains essential for its management, it can contribute to ventilator-associated lung injury. Piezo2, a key mechanosensitive channel, plays a critical role in sensing mechanical stress; however, its clinical relevance in ARDS severity remains unclear.

Patients were included based on predefined inclusion criteria, and bronchoalveolar lavage fluid (BALF) samples were collected from them within 24 h of ICU admission. Piezo2 levels were measured using ELISA.

Among 142 patients (26 non-ARDS, 116 ARDS), Piezo2 levels in BALF were significantly elevated in the ARDS group (mean difference = 30.46; 95 %CI: 9.73-51.20; P < 0.01) and were positively associated with ARDS severity (OR = 1.024, 95 %CI: 1.014-1.034, P < 0.001)). Piezo2 levels showed a significant negative correlation with PaO₂/FiO₂ ratios (r = -0.46; P < 0.001). The ROC analysis demonstrated strong discriminatory power of Piezo2 for identifying moderate-to-severe ARDS (AUC = 0.87; 95 % CI: 0.82-0.93). Compared to the Piezo2low group, patients in the Piezo2high group required higher respiratory rates (18 ± 4.7 vs. 16 ± 3.8 breaths/min; P = 0.03), higher PEEP levels (9.56 ± 2.43 vs. 7.56 ± 2.12 cmH₂O; P < 0.01), and had 4.8 fewer ventilator-free days at day 28 (P < 0.01). However, no significant difference was observed in all-cause mortality between the groups (OR = 1.003; 95 % CI: 0.993-1.014; P = 0.52).

Piezo2 levels in BALF were significantly higher in patients with ARDS compared to those without ARDS, and correlated with greater ventilatory support and fewer ventilator-free days at 28 days.