PET/CT: First-Line Examination to Assess Disease Extent of Disseminated Coccidioidomycosis. Coccidioidomycosis is an infection caused by inhalation of the Coccidioides fungus. Most infections remain subclinical or are confined to the pulmonary system. Disseminated disease is rare. Traditionally, a combination of imaging modalities has been used to determine disease extent. We suggest (18)F-FDG PET/CT as a single first-line imaging examination to assess disease extent. We present a case of disseminated coccidioidomycosis to the lung, mediastinum, soft tissues, and skeletal system. To our knowledge, no prior case reports demonstrate such widespread disease using PET/CT.