Learning Radiology xray montage


  • Caused by actinomyces israeli, a gram+ pleomorphic anaerobic bacterium related to the morphology of a fungus and Mycobacterium—not acid fast

  • At one time, it was the most common pulmonary fungal disease

  • White or yellow “sulfur granules” in exudate are really mycelial clumps

  • Rod shaped form is found “normally” in dental caries, gingival margins, tonsillar crypts and GI tract

  • People with very poor dental hygiene and those that are immunosuppressed are predisposed

  • Affects mandibulofacial area, intestinal tract and lung, in that order


  • Osteomyelitis of the mandible — with soft tissue mass – “lumpy jaw”


  • Resembles Crohn’s disease

  • May produce rupture of a hollow viscous, especially appendix

  • May produce fistula formation


  • Consolidation which extends across fissure — peripheral and lower lobe

      • DDX for lung consolidation which extends through chest wall:

        • Blastomycosis

        • TB

        • Crytococcosis

  • Abscess

  • Empyema

  • Osteomyelitis of the rib — wavy periosteal reaction, rarely rib destruction

  • Draining chest wall sinuses

  • If chronic, it results in severe fibrosis