What you want to ask for is probably an infectious disease (ID) specialist. This is it's own specialty, but in many areas, an internist, pulmonologist or other doc will pick it up as a sub-specialty.
You own pulmonologist can also send your specimens to National Jewish Health in Denver, then telephone consult with someone there to work out your plan. (That is what my own ID & pulmonologist in Minnesota did when they were unsure of what to do next with my infection.)
Sue