Correct!
1. Acute coccioidomycosis infection
The patient’s presentation and imaging are relatively non-specific, but are consistent with acute coccidioidomycosis. The mild eosinophilia is consistent with that diagnosis. Bacterial pneumonia can cause consolidation, but the patient has no symptoms of such an infection, and the rather extensive lung opacities, if due to bacterial pneumonias, would be expected to result in at least some symptoms, such as productive cough and fever. The chest CT shows no features of fibrotic lung disease, such as traction bronchiectasis, intralobular lines, architectural distortion, and honeycombing, excluding the diagnosis of usual interstitial pneumonia / idiopathic pulmonary fibrosis. Aspiration pneumonia is a consideration, but the patient does not have predisposing factors for this condition, and the lung opacities do not show a bronchiolitis pattern or airway thickening, nor are they preferentially dependently distributed. Bronchogenic malignancy is unlikely, typically appearing as a solitary poorly defined nodule or mass, but occasionally unusual imaging patterns can be seen, particularly multicentric adenocarcinomas, often when a mucinous histology is present. This consideration remains within the differential diagnostic possibilities when fairly extensive lung opacities are encountered within a minimally asymptomatic patient, but is still less likely that an acute fungal infection in a patient with rash and eosinophilia living in an endemic region.
The patient was referred to infectious disease, who felt her presentation was consistent with acute coccioidomycosis infection complicated by a hyperimmune response. The reason for her negative serological testing was unclear but was attributed to control of fungal growth. Anti-fungal therapy was not prescribed as it was felt the patient’s immune response was adequate and protective. She was advised to follow up with infectious disease in 3 months with Coccioides serologies to be repeated. Her primary care physician planned to follow up on the patient’s elevated alkaline phosphatase level with an outpatient bone scan.
The patient returned to her infectious disease physician just under 3 months later. She reported feeling well, with her rash, muscle aches and fatigue entirely resolved. Repeat Coccioides serology was negative. Her chest CT was repeated (Figure 3).
Figure 3. Left: Representative images from the repeat axial enhanced chest CT displayed in lung windows. Right: video ot repeat chest CT scan in lung windows.
Regarding the follow up chest CT (Figure 3), which of the following statements is most accurate? (Click on the correct answer to be directed to the sixth of twelve pages)