Monitoring Treatment Responses in Patients with Pulmonary TB Using Serial Lung Gallium-67 Scintigraphy

OBJECTIVE. Gallium-67 scintigraphy is more sensitive than chest radiography in a single concurrent detection of pulmonary tuberculosis (TB). As for inflammation, the intensity of pulmonary uptake of 67Ga citrate theoretically is a function of the inflammation level in the lung. To maximize clinical applicability of 67Ga scintigraphy in the evaluation of pulmonary TB, we prospectively assessed serial qualitative associations between intensity of the uptake of 67Ga citrate and the severity of lung inflammation, reflected by the burden of Mycobacterium tuberculosis in the sputum of patients undergoing anti-TB chemotherapy.SUBJECTS AND METHODS. Each enrolled patient had chest radiographic, microbiologic, 67Ga imaging, and semiquantitation of sputum acid-fast bacillus (AFB) assessments before and at the third and sixth months after receiving anti-TB chemotherapy. The burden of pulmonary M. tuberculosis (presumably, in proportion to the semiquantitation of AFB in sputum) and the intensity of 67Ga citrate uptake...