Correct!
5. No particular diagnosis can be offered
Any of the possibilities mentioned are possible explanations for the patient’s condition, but data sufficient to establish a specific diagnosis is lacking. Obtaining Actinomyces israelii from both the lower extremity skin biopsy and from bronchoscopy raises the possibility of a systemic infection, particularly in the context of immunosuppression, but the chest CT findings are certainly atypical in this regard and the bronchoscopic findings could merely reflect contamination. Furthermore, the pulmonary hypertension remains unexplained by actinomycosis. The ventilation-perfusion scintigraphy results suggest thromboembolic disease, which could also explain the pulmonary hypertension, but the lung findings at chest CT are inconsistent with thromboembolic disease. Vasculitis and a collagen vascular disease both could explain the pulmonary hypertension as well as the patient’s presentation, but the presence of Actinomyces israelii and the pulmonary findings at chest CT are inadequately accounted for by these disorders. Ultimately more investigation is required.
Given the discordant data, the patient underwent CT pulmonary angiography (Figure 4) to assess for acute or chronic thromboembolic disease.
Figure 4. Static representative images from the axial enhanced CT in soft tissue windows (A-F) and lung windows (G-O). Lower left: video of CT in soft tissue windows. Lower right: video of CT in lung windows.
Which of the following represents the most accurate assessment of the chest CT findings?(Click on the correct answer to proceed to the eighth of twelve pages)