Thus, ABPA must be distinguished from Invasive aspergillosis, which occurs in immunocompromised patients Aspergillomas, which are collections of Aspergillus in patients with established cavitary lesions or cystic airspaces Aspergillus pneumonia, which is rare and occurs in patients who take low doses of prednisone long term (eg, patients with chronic obstructive pulmonary disease) Although the distinction can be clear, overlap syndromes have been reported.