Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Round pneumonia
- Radiologic Findings
- Chest PA shows an approximately 2.5 cm, slightly ill-defined, oval, increased opacity in the right upper lung field. On closer inspection, an ill-defined increased opacity is also suspected in the medial aspect of the right lower lung field. Low dose chest CT scan shows an approximately 2.2 cm, slightly ill-defined, round, nodular opacity in the right upper lobe. Follow-up chest PA taken three days later shows an increased size of the oval lesion in the right upper lung field, seen as a large round consolidation with air bronchograms.
The ill-defined increased opacity in the medial aspect of the right lower lung field has also aggravated, and a small amount of bilateral pleural effusions have developed. The patient was treated with antibiotics, and follow-up chest PA taken one month later shows a near-complete regression of the previously seen increased opacities in the right upper and lower lung fields, leaving fibrotic scars behind.
- Brief Review
- Round pneumonia, which can mimic solitary pulmonary nodules, comprises less than 1 % of all “coin lesions” and was first reported in the radiology literature in 1954. It is usually described in children but occasionally can be seen in adults as well. In the presence of a pulmonary nodule, round pneumonia should be suspected, particularly if no previous images are available, a rapid growth is observed, or there are signs of infection. The main differential diagnosis is lung cancer, but biopsy should be reserved for lesions that persist despite adequate medical treatment.
Patients present with varying degrees of symptoms, from acute or subacute symptoms of community-acquired pneumonia to no symptoms. The most common pathogen is known to be Streptococcus pneumoniae.
On chest radiograph, a rounded lesion is noted; air bronchograms may be present, but only in approximately 17% of cases. Recent chest scans are often helpful; 2-3 cm lesions that appeared in the last 2-6 weeks are more likely to be infectious rather than neoplastic.
On CT, heterogeneous mass of soft-tissue attenuation, possibly with a spiculated margin, air bronchograms, pleural thickening, or satellite lesions, may be seen.
In conclusion, round pneumonia should be suspected in young, adult patients who present with a pulmonary mass with no other findings suggestive of malignancy, especially when he or she has signs and symptoms of respiratory infection.
- References
- Wagner AL, Szabunio M, Hazlett KS, Wagner SG. Radiologic Manifestations of Round Pneumonia in Adults. AJR 1998;170:723-726.
Garland J, Lieberman G. Round Pneumonia in Adults. Retrieved May 18, 2015, from http://eradiology.bidmc.harvard.edu/LearningLab/
respiratory/Garland.pdf
Vilar J, Domingo ML, Soto C, Cogollos J. Radiology of bacterial pneumonia. European Journal of Radiology 2004;51:102-113.
- Keywords
- Lung, Infection, Bacterial infection,