@mokie @reneemc An induced sputum sample is done in office if someone has a difficult time producing a sputum sample. 7%+ saline is generally used. So I would think that the hyper saline does not change the sputum significantly. My understanding for monitoring MAC et al., comes down to not only frequent sputum samples but also radiology (CT scans) and clinical symptoms.

7% saline by itself does not kill pathogens but it creates an environment that makes it harder for bacteria to thrive. Inhaled saline helps with clearance, which reduces bacterial load. The bacteria are sneaky and can form biofilms making them resistant to antibiotics. So the more bacteria you can get rid of frequently the better.