Can tumor necrosis factor-associated apoptosis-inductive ligand be used as a biomark in diagnosis of acute pulmonary embolism and prediction of disease severity?

INTRODUCTION AND AIM: Pulmonary embolism (PE) is a potentially life-threatening condition that occurs when thrombotic fragments—usually originating from the deep veins of the lower extremities—block the pulmonary artery or its branches. In clinical practice, the diagnostic process typically begins with suspicion, especially in patients presenting with unexplained dyspnea and tachycardia, alongside a normal chest X-ray. Risk stratification based on clinical presentation and predisposing factors allows patients to be grouped into low, intermediate, or high probability categories, which can guide diagnostic and therapeutic decisions. This study investigates whether Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) levels could be a useful biomarker in diagnosing or excluding acute pulmonary embolism. Additionally, we aimed to assess whether TRAIL levels might reflect disease severity. To explore this, we categorized hemodynamically stable patients with acute PE using the Simplified Pulmonary Embolism Severity Index (sPESI) and analyzed the relationship between sPESI classification, serum TRAIL levels, and Pro-BNP values. MATERIAL AND METHODS: The study included 65 patients diagnosed with acute PE—confirmed via pulmonary CT angiography—who were admitted to the Chest Diseases Department at Selçuk University Faculty of Medicine between October 1, 2022, and May 1, 2024. A control group of 65 individuals was also enrolled. Data were analyzed using IBM SPSS Statistics (version 27.0, IBM Corp., Armonk, NY, USA). The Kolmogorov-Smirnov test was used to assess normality. Continuous variables are reported as mean ± standard deviation or median (interquartile range), while categorical variables are expressed as counts and percentages. To examine the diagnostic utility of TRAIL and Pro-BNP, a receiver operating characteristic (ROC) analysis was performed, and cut-off values were determined using the Youden index. RESULTS: The mean age of participants was similar between the control (62.6 ± 11.3 years) and PE (60.9 ± 15.9 years) groups (p=0.887). Gender distribution was identical: 40% female and 60% male in both groups (p=1.000). Significant differences were observed in Pro-BNP and TRAIL levels, with higher TRAIL values recorded in the PE group (p=0.016). Among patients with PE, those classified as low-risk based on sPESI had average TRAIL levels of 482.8 ± 1396.1 ng/mL, while the high-risk group showed lower levels (365.2 ± 1318.6 ng/mL), which was statistically significant (p=0.044). For Pro-BNP, levels rose markedly from 238.6 ± 334.4 pg/mL in the low-risk group to 2503.5 ± 4245.4 pg/mL in the high-risk group (p<0.001). CONCLUSION: These findings indicate that TRAIL may be a promising biomarker for both diagnosing acute PE and estimating disease severity. Given TRAIL's potential role in inflammatory and thrombotic pathways, it may contribute to clinical decision-making in the future. However, larger, multi-center studies with long-term follow-up are needed to validate these results and determine how TRAIL might be integrated into diagnostic algorithms more reliably.