diagnostic role of mediastinoscopy in isolated mediastinal tuberculous lymphadenopathy

Isolated mediastinal tuberculous lymphadenopathy without a pulmonary parenchymal lesion is still a diagnostic challenge. The diagnostic yield of noninvasive methods is low in these cases. From July 1995 to June 2002, 39 patients with suspected isolated mediastinal tuberculous lymphadenopathy without any demonstrable pulmonary parenchymal lesion and with negative diagnostic noninvasive methods underwent mediastinoscopy as a final diagnostic step for diagnosis. These cases where reviewed retrospectively. The mean age was 36.3 years [range, 9 to 64 years] and 24 were male. The most common symptom was cough in 32 patients and 7 were asymptomatic. In all cases chest x-ray [CXR] and computed tomography [CT] chest showed isolated mediastinal lymphadenopathy with Involvement of the right paratracheal nodal group in 33 cases. In 27 patients [group 1], Multiple biopsies of 2 to 4 mediastinal nodal groups diagnosed tuberculous lymphadenitis in all patients; in 4 of them nonspecific inflammatory nodes were also sampled. The diagnostic yield [sensitivity] in group 1 was 100%. In 12 patients [group 2] who had biopsies of one mediastinal nodal group, the diagnosis could not be established in 3 patients and the diagnostic yield was 75%. In both groups the diagnostic yield of mediastinoscopy was 92%. It was concluded that when used effectively, mediastinoscopy was acceptable as a final diagnostic step in patients with suspected isolated mediastinal tuberculous lymphadenopathy without a pulmonary parenchymal lesion because of its high diagnostic yield