Mediastinal Lymphadenopathy: Associations Between Computed Tomography Characteristics and Final Etiological Diagnoses in 200 Patients

Background: Despite recent technological advances in the diagnostic evaluation of mediastinal lymphadenopathy, access to advanced diagnostic procedures remains limited in our setting. Objective: This study aimed to describe the etiological profile of mediastinal lymphadenopathy and to assess the statistical associations between computed tomography (CT) characteristics of mediastinal lymph nodes and final etiological diagnoses. Materials and methods: This retrospective observational study was conducted in the Department of Pulmonology at Moulay Youssef University Hospital, Salé, Morocco, over a two-year period. It included all eligible hospitalized patients with mediastinal lymphadenopathy detected on chest CT during the study period. Demographic, clinical, radiological, bronchoscopic, pathological, and follow-up data were collected from medical records. Final diagnoses were established by histopathological confirmation whenever available and, in the remaining cases, by a multidisciplinary assessment integrating clinical, radiological, biological, exposure-related, and follow-up data. Associations between lymph node characteristics and final etiologies were analyzed using the chi-square test, Fisher’s exact test, and the Mann-Whitney test, as appropriate. Results: A total of 200 patients were included. The mean age was 56 ± 14 years (range: 19-94 years), and women represented 57% of the cohort. Sarcoidosis was the most frequent etiology, observed in 75 patients (37.5%), followed by metastatic lymphadenopathy in 45 (22.5%), reactive lymphadenopathy in 36 (18.0%), tuberculosis in 20 (10.0%), sequelae-related lymphadenopathy in 11 (5.5%), lymphoma in 10 (5.0%), and silicosis in three patients (1.5%). Several CT characteristics were significantly associated with specific etiologies. Sarcoidosis was most frequently associated with bilateral involvement, symmetric distribution, regular margins, homogeneous density, absence of compression, and preferential involvement of stations 3, 4L, 10R, and 10L. Metastatic disease was most frequently associated with unilateral or asymmetric distribution, irregular margins, heterogeneous density, and compression. Conclusions: This study identified significant associations between selected CT characteristics of mediastinal lymphadenopathy and final etiological diagnoses. These findings may contribute to a more structured radiological assessment and help support the initial etiological orientation in clinical practice. However, they should be interpreted cautiously in light of the retrospective design, the heterogeneous cohort, the absence of systematic histopathological confirmation in all patients, and the lack of formal diagnostic accuracy analyses.