Radiological Spectrum of Mediastinal Lymphadenopathy in Adults

Background: There is an increasing number of adult patients with mediastinal lymphadenopathy without any significant pulmonary lesion, at least on plain X-ray of the chest, attending our medical outpatient department (OPD).Sometimes, invasive procedures for histopathological diagnosis are difficult, and the radiological investigations with other clinical findings might help to diagnose the disease.So, we wanted to correlate the radiological findings of patients with the diagnosis of the disease.Objectives: To analyze the anatomical site and pattern of involvement of mediastinal lymph nodes on computed tomography (CT) scan findings with the diagnosis of disease.Results: A total of 32 adult patients (24 male, 8 female) of mediastinal lymphadenopathy without any significant pulmonary lesion were included in the study.Chest X-ray and CT scan of the chest were evaluated for each patient at the time of inclusion in the study.Clinical features, tuberculin test, blood test, and histopathological test were done to confirm the diagnosis of the disease in each patient.On CT scan chest, in the tubercular lymphadenopathy group (n = 21, 65%), right paratracheal nodes (86%) were most commonly involved, followed by subcarinal nodes (62%), and peripheral rim enhancement with low attenuation at the center of the node was the most frequent pattern (76%).Calcification was seen in 19% of cases.In the lymphoma group (n = 8, 25%), paratracheal nodes, followed by perivascular, subcarinal, and extramediastinal sites, were involved.In sarcoidosis (n = 1), hilar lymphadenopathy with lung involvement was seen.Conclusion: Rightparatracheal nodes (86%) were the commonest site of involvement, followed by subcarinal nodes (62%), and peripheral rim enhancement with low attenuation at the center of the node was the most frequent pattern in tubercular mediastinal lymphadenopathy.Extensive adenopathy at paratracheal, perivascular, and extramediastinal nodes, which are asymmetrical, large with pressure effect on adjacent structures, no calcification, and homogeneous, was more common in lymphoma.Bilateral symmetrical hilar involvement and homogeneous patterns were more common in sarcoidosis.Tuberculosis is still the most common cause of mediastinal lymphadenopathy in India.