Lung and Nodal Involvement in Nontuberculous Mycobacterial Disease: PET/CT Role.

INTRODUCTION: Systematic use of (18)F-FDG PET/CT has the potential to simultaneously assess both pulmonary and lymph node involvement in nontuberculous mycobacterial (NTM) lung infection.

OBJECTIVE: The aim of the study was to evaluate the role of (18)F-FDG PET/CT in the assessment of both mediastinal lymph nodes and lung involvement in NTM patients compared with active tuberculosis (TB) patients.

METHODS: 26 patients with pulmonary NTM disease were selected; six consecutive patients had undergone (18)F-FDG PET/CT and data was compared with 6 active TB patients.

RESULTS: NTM exhibited different radiological lung patterns with an average SUV max value at PET/CT scan of 3,59 ± 2,32 (range 1,14 to 9,01) on pulmonary lesions and a mean value of SUV max 1,21 ± 0,29 (range 0,90 to 1,70) on mediastinal lymph nodes. Pulmonary lesions in TB showed an average SUV max value of 10,07 ± 6,45 (range 1,20 to 22,75) whilst involved mediastinal lymph nodes exhibited a mean SUV max value of 7,23 ± 3,03 (range 1,78 to 15,72).

CONCLUSIONS: The differences in PET uptake in a broad range of lung lesions and lymph nodes between NTM and M. tuberculosis patients suggest a potential role for PET/CT scan in the diagnosis and management of pulmonary mycobacterial disease.