Correct!
5. The pulmonary CTA shows subtle inhomogeneous attenuation involving the lung parenchyma
The CT pulmonary angiography study is not normal. Enlargement of the main pulmonary artery and right ventricle- consistent with pulmonary hypertension and confirming the findings at echocardiography- is present. The central pulmonary arteries show no evidence of acute or chronic thromboembolic disease. The lung parenchyma shows no infiltrative abnormalities, such as ground-glass opacity, consolidation, or features of fibrotic lung disease to explain the patient’s oxygenation abnormalities. The pulmonary CTA shows normal hilar and mediastinal structures- no peribronchial or mediastinal lymph node enlargement is present. Review of the lung parenchyma shows bilateral inhomogeneous lung opacity, with areas of decreased and increased attenuation (Figure 5).
Figure 5. Axial enhanced thoracic CT displayed in a relatively wide lung window width (A-F) shows multifocal, bilateral, inhomogeneous lung opacity manifest as areas of relatively increased attenuation compared with areas of relatively decreased attenuation (lung parenchyma between arrowhead pairs).
Note that the pulmonary vessels appear rather small in the areas of decreased attenuation- this finding can reflect hypoxic vasoconstriction, although causes of pulmonary arterial obstruction, such as thromboembolic disease, and pulmonary hypertension, may rarely produce this finding.
The patient was found to have an elevated erythrocyte sedimentation rate as well as low-grade anti-nuclear antibody positivity and her anemia was thought to be hemolytic in etiology.
Which of the following represents an appropriate step for the evaluation of this patient? (Click on the correct answer to proceed to the fifth of six panels)