Mediastinal tuberculous lymphadenitis: CT manifestations.

An analysis was done of computed tomographic (CT) scans of 23 Korean patients who had presented with a mediastinal or hilar mass on plain chest radiographs and had subsequently been found to have tuberculous lymphadenitis. Most patients were young adults. Findings of pulmonary tuberculosis were seen on plain radiographs in 14 patients. On CT, findings were of an overwhelming preponderance of involvement of the right paratracheal and tracheobronchial nodes. After injection of contrast medium, nodes larger than 2 cm in diameter invariably showed central areas of relative low density and peripheral rim enhancement. Enhanced walls were usually irregular in thickness. Some smaller nodes did not show low-density areas, but instead showed varying degrees of homogeneous enhancement. Although metastatic nodes can be of low density, experience in this study suggests that mediastinal lymphadenopathy in a young adult with the CT findings described above is characteristic enough to support a diagnosis of tuberculosis.