Tuberculosis: frequency of unusual radiographic findings.

The changing pattern of the radiologic presentation of tuberculosis was noted in a review of 100 consecutive cases of pulmonary tuberculosis. Active tuberculosis was not suggested as a radiologic diagnosis in 43% of the patients. Of the 100 cases, only 66 had characteristics of reactivation tuberculosis (i.e., minimal upper lobe infiltrate or more advanced cavitary disease). Of the other 34 patients, 18 had less usual presentations, making the radiographic diagnosis difficult. The remaining 16 patients had radiographic patterns quite unusual for tuberculosis, including masslike densities resembling carcinoma; chronic infiltrates in a lower lobe; miliary tuberculosis, either superimposed on diffuse interstitial lung disease or associated with a diffuse lung pattern atypical for miliary disease; and normal chest radiograph.