F-18 FDG UPTAKE IN TUBERCULOSIS

Two patients are described who showed abnormal fluorine-18 fiuorodeoxy glucose (F-18 FDG) uptake that was due to benign disease, specifically tuberculous lymphadenitis and pneumonitis. The first patient had ulce ration and oozing of the left nipple that was related to Paget's disea se. An F-18 FDG PET, whole-body scan, which was performed for staging, showed no breast uptake. However, there was intense multifocal uptake in mediastinal, supraclavicular, and para-aortic areas that was confi rmed radiologically to represent widespread lymphadenopathy. Pathologi c examination of a mediastinal lymph node showed active tuberculosis. The second patient showed intense focal F-18 FDG uptake in mediastinal and supraclavicular areas and para-aortic lymphadenopathy due to non- Hodgkin's lymphoma. In addition, there was abnormal F-18 FDG lung upta ke that revealed the presence of acid-fast bacilli on bronchial ravage . Intense focal F-18 FDG uptake in widespread lymphadenopathy or in th e lung could be caused by infectious diseases such as tuberculosis. Th is possibility should be considered when whole-body scans of patients with cancer are interpreted, especially in those with a high incidence of infectious disease.