“…To our knowledge, this is the first report of 18 F-FDG PET/ CT imaging of an infection caused by M. simiae in a human patient. 18 F-FDG PET/CT cannot differentiate among the different causes of necrotizing cervical lymphadenitis, which can be caused by different bacteria, including Mycobacterium tuberculosis, Mycobacterium avium intracellulare, Histoplasma capsulatum, Coccidioides immitis, Bartonella henselae, Francisella tularensis, Chlamydia trachomatis L2, Yersinia pseudotuberculosis and Yersinia enterocolitica; and nonbacterial causes such as viral pathogens (e.g., Herpes simplex, Parvovirus B19) [13][14][15], lymphoma, metastatic carcinoma [15] and Kikuchi disease [16][17][18]. However, in this case, the PET/CT whole-body scan was very helpful in identifying multiple sites of infection within the neck, in ruling out disseminated infection or infectious foci outside the neck, and in guiding biopsy and subsequent therapy.…”