Longtime smoker with fever and cough.

Our appreciation is extended to Dr. Daniel Sova, Indiana University Department of Radiology, for contributing this case.

Longtime smoker with fever and cough.

Longtime smoker with fever and cough.

Longtime smoker with fever and cough.

Longtime smoker with fever and cough.

• Lung abscess
• Malignancy (bronchogenic carcinoma, lymphoma, metastases)
• Septic emboli (with lung abscess)
• Wegener's granulomatosis
• Fungal infection (histoplasmosis)
• TB

Still unresolved is the status of the smaller R apical lesion.  The patient was treated for his lung abscess and was lost to follow up despite multiple attempts to further evaluate and monitor this lesion.  Over a year later, the patient returned with new complaints.

Click these images to enlarge them. 

Findings:  The site of the lung abscess shows a scar.  There is now a large malignant R apical mass that abuts the chest wall.

Longtime smoker with fever and cough.

Key points - Lung abscess:

• Inner cavity is irregular/nodular/spiculated in cancer but smooth or shaggy in abscess. Outer wall is thick and irregular.
• Cavity wall is usually greater than 4mm.If the wall is greater than 15mm, suggests malignancy. Less than 4mm thick wall favors cystic lesions (bulla, LAM, pneumatocele, coccidiomycoses)
• Often contains air-fluid levels ~75%, though air fluid level is not specific for abscess. These can be seen with invasive aspergillosis, cancer, and sometimes Wegener's.
• It is very common to see reactive mediastinal and hilar lymphadenopathy.
• Time course guides diagnosis - acute processes favor infection or trauma, subacute or chronic favors malignancy or immunologic.
• Definitions:
  • Abscess - collection of pus in the lung with formation of a new cavity
  •  Empyema - collection of pus in the pleural space (or other anatomic space)
• Most common cause of abscess is aspiration pneumonia with abscess formation usually occurring 7-14 days after inciting event.
• Treatment is antibiotics (clindamycin) for several weeks. Treatment of empyema on the other hand involves thoracostomy tube and antibiotics.

1. Mayo Clinic Proceedings June 2003 vol. 78 no. 6 744-752.
2. Up-to-date. Lung Abscess. August 8, 2011.

Longtime smoker with fever and cough.