[High resolution computerized tomography in pulmonary tuberculosis with negative sputum bacilloscopy]

Pulmonary tuberculosis with negative sputum bacilloscopy involves diagnostic difficulties when there are not available liquid culture media due to the slow growth of Mycobacterium tuberculosis in the traditional culture media, and also due to the need for carrying out invasive examinations.

Evaluate the high resolution computerized tomography findings (HRCT) in patients with pulmonary tuberculosis and negative bacilloscopy of sputum.

Prospectively 28 patients (12 with active tuberculosis and 16 with inactive tuberculosis) were evaluated through HRCT, assessing the following findings: centrolobular nodules, multiple branched linear structures, macronodules, cavitation, consolidation, enlargement of interlobular septums, ground-glass change, bronchiectases, emphysema, broncovascular distortion, fibrotic changes, calcified mediastinal adenopathies, parenchymous calcification, pleural enlargement, and pleural effusion.

The findings that were associated significantly to the active disease were: consolidation (67%), macronodules (67%) and centrolobular nodules (67%). The presence of centrolobular nodules and/or consolidation had a sensitivity of 83% and a specificity of 87%. The findings significantly associated to inactive disease were bronchiectases (87%) and broncovascular distortion (62%).

Our results support the value of HRCT in patients with pulmonary tuberculosis and negative sputum bacilloscopy, since the finding of centrolobular nodules and/or consolidation has good sensitivity and specificity for the diagnosis of active pulmonary disease.