Necrotizing Pneumonia, Pulmonary Abscess, and Lung Gangrene

Necrotizing pulmonary infections span a continuum, most notably including necrotizing pneumonia, pulmonary abscess, and lung gangrene. Necrotizing pulmonary infections usually are caused by anaerobic bacteria, mixed flora, and gram-negative organisms. The spectrum of causative organisms is thus different from that of community-acquired pneumonia. Each subtype within the spectrum of necrotizing pulmonary infections has unique history and imaging features that can help the diagnostic radiologist to differentiate these entities, display the extent of parenchymal lung damage, and suggest empiric treatment before formal bacterial diagnosis.