@mrf5629...When the doctor chooses not to prescribe an anti-biotic, it is hard to understand why. Zpak works for me as well. You may want to request that your sputum sample be sent for evaluation to prove an infection. You could also increase water intake and take Mucinex to thin your mucus while waiting.
Since Bronchiectasis is a chronic disease, your doctor may want to keep anti-biotics for severe infections. He expects you to live a long time and need them in the future. keep up the nebulizer and airway clearance.