I would go to your family doctor and he can make the test, if you are allergic against aspergillus, (in Germany the test is called the IGE-levels). If you are, that could be the reason for your cough and you could give the test to the cf-doc for further medication. If you are not allergic, ok, and you don´t have to tell him that he was right in this case...
Uli,43,Germany