(18)F-FDG PET/CT in tuberculosis: an early non-invasive marker of therapeutic response.

Objective: To evaluate the potential of (18)F-fluoro-deoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) for early therapeutic intervention in patients with probable or confirmed tuberculosis (TB).

Methods: Twenty-one consecutive human immunodeficiency virus negative patients were prospectively included. All patients underwent (18)F-FDG PET/CT before and after 1 month of anti-tuberculosis treatment. The maximum standardised uptake value (SUV(max)) of the most (18)F-FDG avid lesions was recorded.

Results: The median age of patients was 36 years (range 18-84); 33.3% were male, 80.9% were born in endemic countries, and 23.8% had a past history of TB. TB was confirmed on culture in 8, on histology in 9 and on the basis of clinical symptoms in 4 patients. (18)F-FDG PET/CT detected active pulmonary TB (n = 1), extra-pulmonary (n = 10) or both (n = 10). The second (18)F-FDG PET/CT showed reduced radiotracer uptake intensity in 19 of 21 patients, with a median percentage decrease of SUV(max) of 31% (range 2-84). Two patients showed no improvement. TB was ruled out in one patient during follow-up; the final diagnosis was a non-Hodgkin's lymphoma. The other patient was smear-positive for 3 months.

Conclusion: (18)F-FDG PET/CT allows an easy evaluation of early therapeutic response in patients with TB, particularly extra-pulmonary TB.