IL33 and Pleural effusion: In the future, we will collect additional samples, including plasma, pleural effusion, and BALF samples, to examine the predictive value of IL-18, the IL-18/IL-38 ratio, and IL-33 for PPE and to determine their potential as biomarkers for the differential diagnosis of PE and the rapid differentiation of pathogens, aiming to uncover more potential clinical applications.