Tehran University of Medical Sciences (TUMS) Academic Journal of Surgery 2423-3218 6 1 2023 12 10 17 23 Ali Biharas Monfared Lung Transplantation Research Center, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran Farahnaz Sadegh Beigee Lung Transplantation Research Center, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran Niloufar Alizadeh Department of Biostatics, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran Mehdi Kazempour Dizaji Department of Biostatics, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran Parizad Sinaei Tobacco Prevention & Control Research Center, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2023 04 10 Background: In the treatment of pleural empyema, medical therapy is typically sufficient for the 1st or 2nd stage. However, surgical intervention becomes the optimal modality in the 3rd stage. A significant number of patients experience delayed diagnosis and treatment, leading to the conversion of non-surgical pleural empyema into complicated surgical empyema. Methods: A cross-sectional study was conducted on patients with pleural empyema who were admitted to NRITLD in Tehran from 2015 to 2016. Initially, 66 patients were selected; however, after the exclusion of 12 patients, a total of 54 patients were included in the study. Results: Delays were attributed to the medical system in 62% of cases and to the patient in 29% of cases. The median (IQR) of the total delay time attributed to the system was 38 (25) days. No significant difference was found in the median of delayed referrals between genders. A significant correlation was observed between the interval of the first and last visit and the interval between the onset of symptoms and chest x-ray (CXR), as well as the interval between the performance of CXR and the insertion of chest tube drainage (CTD). Conclusions: The delay in referral and treatment can be attributed to the patient, practitioners, or both. In this study, it was found that the medical system is the primary cause of delay, primarily due to the long waiting times for admission and operation in hospitals. Patients who experience a delay in CXR and CTD insertion will face a significant delay in referral and their course of treatment. It is suggested that delayed referral could be prevented by providing patients with basic medical education, offering specialized training to general  practitioners for early referral, and managing waiting lists effectively. https://ajs.tums.ac.ir/index.php/ajs/article/view/234 https://ajs.tums.ac.ir/index.php/ajs/article/download/234/111