Bacterial Pneumonia with Abscess – CXR

Table of Contents

Table of Contents

Published February 2021

Samantha King, MD1, Daniel Gergen, MD2

1. Chief Resident, Internal Medicine Residency, University of Colorado, 2. Fellow, Pulmonary and Critical Care Medicine, University of Colorado


  1. Use pleural fissures to determine the location of a right upper lobe pneumonia and abscess.
  2. Construct a differential diagnosis for cavitary lung lesions

Teaching Instructions

Plan to spend 5-10 minutes familiarizing yourself with the animations of the PowerPoint and the key findings of this chest X-ray.

Present the image either by expanding the window (bottom right) in a browser or downloading the PowerPoint file (downloading is recommended).  Have the image pulled up in presenter mode before learners look at the screen to avoid revealing the diagnosis.  Ask a learner to provide an overall interpretation.  Then advance through the animations to prompt learners with key questions and reveal the findings, diagnosis, and teaching points.

Instructions: Ask a learner to provide an overall interpretation.  You can go back to prior graphics and questions by using the back arrow or scrolling back on the mouse wheel.

Official CXR Read: Interval development of sub-pleural mass-like consolidative opacity in the anterior and posterior segments of the right upper lobe. Findings are suspicious for infectious pneumonitis but may also represent malignancy.

Diagnosis: Right upper lobe bacterial pneumonia with abscess.

Teaching: The primary objective of this image is to identify a consolidative pattern with a cavity and localize it to a distinct lobe of the lung.  This can be clinically valuable in distinguishing old from new or evolving processes and can aid a provider in correlating related pathology or risk factors (e.g. previously identified suspicious nodule or history of possible aspiration) in a way that will more accurately tie together the clinical presentation.  This case demonstrates a dense RUL consolidation with a cavity visible in the lateral view.  There is also some distortion of the minor fissure and evidence of volume loss in the right upper lobe that in this case is likely due to tissue destruction from necrotizing infection. The secondary objective is to generate a differential for lung cavities and integrate the clinical stem and imaging features to determine the likely diagnosis.

Mneumonic for lung cavitations: CAVITY

C: cancer, most commonly:
– Squamous cell carcinoma (SCC)
– cavitary pulmonary metastasis(es)

A: autoimmune; granulomas from
– Granulomatosis with polyangiitis
– Rheumatoid arthritis (rheumatoid nodules) etc.

V: vascular (both bland and septic pulmonary emboli)

I: infection (bacterial/fungal)
Lung abscess / cavitating PNA (acute-subacute)
Septic pulmonary emboli (acute-subacute)
Pulmonary tuberculosis

T: trauma – pneumatoceles (air-filled cavity in the lung)

Y: youth (congenital causes of pulmonary cavitation)

Presentation Board

Take Home Point

  1. The minor fissure separates the right upper lobe from the middle and lower lobes (there is no minor fissure on the left).
  2. The pneumonic “CAVITY” generates a differential for cavitary lung lesions that can be further differentiated by acuity.  


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Goodman, L. R. (2019). Felson's Principles of Chest Roentgenology E-Book: A Programmed Text. Netherlands: Elsevier Health Sciences.

McLoud, Boiselle, & Boiselle, Phillip M. (2010). Thoracic radiology: The requisites (2nd ed., Requisites in radiology). Philadelphia: Mosby/Elsevier.

Brandon Fainstad


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