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Introduction and Objectives Isolated hilar and mediastinal lymphadenopathy (IHML) on Computed Tomography (CT) chest is a frequent incidental finding requiring further evaluation. While benign causes such as sarcoidosis and reactive lymphadenopathy are among the common differentials, concerns remain regarding more serious pathologies such as lymphoma, occult nodal metastases and tuberculosis (TB). Nodal sampling is performed using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) to confirm the diagnosis. We aimed to assess the feasibility of a novel CT-based scoring system based on defined radiological features to predict the likelihood of sarcoidosis in IHML.Methods We conducted a retrospective analysis of 81 patients who underwent EBUS-TBNA for IHML in 2022. A thoracic radiologist, blinded to histopathology results, reviewed CT scans for the following features: nodal distribution (2 points for typical distribution and 1 for atypical), nodal density (1 for high, 0 for normal), peri-lymphatic lung nodules (1 if present, 0 if absent), and features suggestive of other pathologies such as infection or malignancy (0 if present, 1 if absent). A total score of 1 was considered low, and 5 high probability for sarcoidosis. Scores were compared against nodal histology as a form of preliminary validation.Results Of the 81 patients, mean age was 64 years (range 22–90), males 50 (61.7%). 6 patients had a score of 5, of which 4 had confirmed granulomatous lymphadenitis on nodal histology, one was diagnosed with sarcoidosis on wedge lung biopsy after inconclusive EBUS-TBNA, and one patient was treated as sarcoidosis after a multidisciplinary review. 22 patients had a score of 4, of which 20 had granulomatous lymphadenitis. 21 patients scored 3, of which only 3 had granulomatous lymphadenitis, with one treated as sarcoidosis and one diagnosed with TB. In 32 patients with scores of 1 and 2, only 3 had granulomatous lymphadenitis, of which one was confirmed TB. None of the patients had malignancy.Conclusions Our study supports a novel CT scoring system to predict pre-test probability of sarcoidosis in IHML, with preliminary validation in a retrospective cohort. Further prospective studies are required to validate its clinical utility, along with interobserver variability assessment between radiologists.