CT findings of mediastinal tuberculous lymphadenitis

Mediastinal tuberculous lymphadenitis is commonly encountered disease in Korea and especially in adult, differential diagnosis with other mediastinal disease is important. CT findings of tuberculous lymphadenopathy are reported in many articles that enlarged lymph nodes shows central low density with peripheral rim peripheral rim enhancement in contrast enhanced CT scan. Authors analyzed CT findings of 28 cases with mediastinal tuberculous lymphadenitis retrospectively according to lymph node size, shape and enhancement pattern. The results were as follows: 1. Total 28 cases were 10 males and 18 females and the most prevalent age group was the 3rd decade. 2. Enlarged lymph nodes were noted in paratracheal, tracheobronchial, subcarinal and hilar lymph node areas in order to frequency. Unilateral nodal involvement (71.4%) was more common and Rt. side predominance (70%) was noted. 3. On contrast enhanced CT scan, central low density with peripheral rim enhancement was characteristic findings of lymphadenopathy which shows chronic granulomatous inflammation with caseous necrosis in pathology regardless of lymph node size. Even less than 1cm sized lymph node, commonly regarded as normal, shows characteristic central low density area suggesting caseous necrosis in pathology. 4. Mediastinal lymph node enlargement without parenchymal lesions was found in 6 cases (21.4%).