Diagnostic Value of Mediastinal Lymphadenopathy in Differentiating Pulmonary Tuberculosis from Community-Acquired Pneumonia in Children

Background: Diagnosis of childhood pulmonary tuberculosis (TB) is often based on clinical features in combination with radiologic findings because of paucibacillary nature of the disease in children. It may be difficult to make a clinical diagnosis because of the overlapping clinical features of pulmonary TB and community-acquired pneumonia (CAP). On computed tomography (CT) scanning, the presence of typical LAP can suggest TB as a possible cause. Objectives: To compare the features of mediastinal LAPs between two patient groups based on contrast-enhanced chest CT. Methods: A total of 45 pulmonary patients with TB and 38 patients with CAP (aged ≤ 18 years) were enrolled in this retrospective study. The presence and CT features of lymph node involvement and the incidence of associating parenchymal/pleural findings were analyzed in two groups. Results: All patients with TB and 36 of the 38 patients with CAP had at least one mediastinal LAP. There was no significant difference between the two groups according to the incidence of lymph node and multiple site involvement and also involved lymph node stations (P > 0.05). However, lymph node size was larger in the TB group (P = 0.04). Twenty-two percent of patients with TB had mediastinal LAP without parenchymal/pleural involvement. Conclusions: Although the lymph node size was larger in TB group than in CAP group, CT features of mediastinal lymph node involvement overlapped between two groups. Nevertheless, mediastinal LAP without parenchymal/pleural involvement on CT is seen in a significant number of TB patients.