Evaluation of the role of Human Neutrophil Elastase, Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio as Predictive Markers For severity of acute respiratory toxicity Among Patients Admitted to Poison Control Center of Ain Shams University Hospitals.

Background: There are hundreds of xenobiotics that can damage the respiratory system, necessitating mechanical ventilation. Therefore, acute respiratory toxicity may represent a serious condition that can be complicated by acute respiratory distress syndrome (ARDS). This study aimed to evaluate the role of Human Neutrophil Elastase (HNE) as a predictor of acute respiratory toxicity outcome and to compare it with the neutrophil lymphocyte ratio (N/L ratio) and platelet lymphocyte ratio (P/L ratio).

Methods: This prospective study was conducted on adult patients with acute respiratory toxicity admitted to Poison Control Center; Ain shams university hospitals from January 2022 till December 2022. Their HNE, N/L ratio, and P/L ratio levels were assessed twice: first upon admission and again 24 hours later.

Results: Fifty-five patients were enrolled in the study and were classified into ARDS group and non-ARDS group. HNE levels were significantly higher in ARDS patients at both time points with excellent predictive performance. Although the N/L and P/L ratios were significantly elevated in ARDS patients at 30 hours, their diagnostic performance was inferior to HNE. Combining HNE with the N/L ratio offered minimal additional benefit over HNE alone.

Conclusion: HNE Level can serve as predictor of ARDS in acutely intoxicated patients.