대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Septic Pulmonary Embolism

Radiologic Findings

The chest radiograph shows multiple ill-defined nodular opacities or consolidations in both lungs with pleural effusion in both hemithoraces. Chest CT scans show multple, peripheral parenchymal nodules and wedge-shaped consolidations, and some of them have distinct feeding vessels. Final diagnosis was based on radiologic findings and the result of blood culture (Staphylococcus aureus was grown).

Brief Review

The most common sources of septic pulmonary emboli are infected venous catheters, including pacemaker wires, tricuspid valve endocarditis, septic thrombophlebitis and indwelling prosthetic devices. The diagnosis is usually established by positive blood cultures and the presence of an infected source for the emboli. It is worth noting that positive radiographic findings, particularly abnormalities seen on CT, may be visible before blood cultures become positive, and the diagnosis may be first suggested on chest CT.
The usual radiographs and CT scan demonstrate multiple pulmonary opacities. The opacities may occur in any portion of the lungs but are usually maximal in the lower zones. The lesions are usually either round in shape or show the shape of a pulmonary infarct, namely a wedge-shaped density base on the pleura and pointing to the hilum. They may have any size and frequently cavitate, a feature more easily recognized on CT. Air-bronchograms are frequently seen, particularly on CT, in all types of opacity, including the nodular lesions. The combination of multiple peripheral nodules or wedge-shaped consolidations, some of which are cavitated, and a distinct feeding vessel in the appropriate clinical setting is highly suggestive of the diagnosis of septic emboli. Accompanying pleural effusion and empyema are a common feature.

References

1.Armstrong P, Dee P. Infection of the lungs and pleura. In: Armstrong P, Wilson AG, Dee P, Hansell DM. Imaging of diseases of the chest, 2nd ed. St. Louis: Mosby press 1995:165.

Keywords

Lung, Vascular, Infection, embolism,