Hi,
Welcome to the ehealthforum. I am glad to help you out.
I can understand the pain & agony you are going through. You have already done most of the tests which are routinely done for looking the cause of breathlessness.
If you are getting relief from the use of symbicort, then the possibility of asthma is high.
However, pulmonary obstruction should be detected on the spirometry. Iâll suggest getting your haemoglobin checked and the thyroid hormone levels assessed.
Anaemia and hypothyroidism are 2 important general diseases which can cause breathlessness and are usually missed. I sincerely hope this information helps. Take care.