Necrotizing Cervical Lymphadenitis Caused by Mycobacterium simiae in an HIV Positive Patient: Imaging with 18F FDG PET/CT

Mycobacterium simiae is an opportunistic pathogen rarely associated with human disease, although in recent years M. simiae has been detected with increasing frequency in human immunodeficiency virus (HIV) infected patients, usually causing disseminated infection with fever, diarrhea and weight loss. We report the case of an HIV positive man, who was referred for an 18F FDG PET/CT to evaluate a solitary pulmonary nodule. The PET/CT showed incidental large necrotic cervical lymph nodes, compatible with necrotizing cervical lymph adenitis. Biopsy and culture of one of the affected lymph nodes were positive for M. simiae. We present the first report of 18F FDG PET/CT imaging of an infectious process caused by M. simiae in humans.