Could pulmonary fibrosis spread from one lung to a health lung?

Both are affected: Normally, in pulmonary fibrosis both lungs are affected at the tissue level. The x-ray can show one lung more affected than the other. Confusion can occur when a doctor calls an old scar pulmonary fibrosis. In these cases, there should be no further progression of the scarring.

Yes: Pulmonary fibrosis involves both lungs. There is something else going on if it is in only one lung. Check with your lung doc.