Detection of extrapulmonary tuberculosis with gallium-67 scan and computed tomography

We evaluated 23 patients with extrapulmonary tuberculosis (TB) with 67Ga imaging to assess its usefulness in the diagnosis of this condition. We performed computed tomography (CT) in 17 patients to assess CT features of extrapulmonary TB in comparison with findings from 67Ga scans. Nineteen of 23 patients (83%) had positive findings on 67Ga scans. One of five patients with tuberculous mediastinal lymphadenopathy, two patients with cervical lymphadenitis and a patient with renal TB had negative 67Ga scans. It was observed that the detection of previously unrecognized primary foci of TB, without concomitant pulmonary TB, was possible using 67Ga imaging in five patients (22%). The 67Ga scan was relatively sensitive for the localization of extrapulmonary TB. It is suggested that the 67Ga scan could serve as a screening method, when followed by CT and ultrasonography, for the initial detection of occult tuberculous lesions, especially in patients with prolonged fever.