I reviewed it with a pulmonary expert. We are monitoring it.
The CT scan is a much more sensitive test than a chest x-ray. So the "infiltrate", typically appearing as a shadow, may have been there and not evident on the chest x-ray. It would be good for your doctor to review the chest x-ray, with the benefit of hindsight, to see if the infiltrate was there. The other possibility is that the infiltrate was simply not present 2 months ago. Many, but not all infiltrates can develop quickly, often within a span of a day or two.
The key thing now is to get your doctors to commit themselves on what this infiltrate might be, based on size, shape, distribution etc. If you have been acutely ill and now feeling even a little better, it might be reasonable to give the infiltrate a week or so to resolve. If you are still symptomatic with cough, fever, discolored mucus etc, just waiting for resolution would be inappropriate.
If you are not feeling better and your doctor(s) is uncertain about what is going on, you might be wise to see a lung specialist. Perhaps you could run this message by your doctor, as a first step. Be sure to ask your doctor for the official interpretation of the infiltrate on CT scan.
Good luck.
It could be something like pneumonia or collapsed part of your lung. Have you been sick?