Oh my stars! You are the 1st person I’ve found that had what I have. Pulmonary fibrosis from chest radiation. As a result I now have Traction Bronchiectasis. I don’t know what MAC is either. I don’t cough up sputum. I don’t hv chest congestion. If you do start to get congestion you need to get antibiotics to prevent it from turning into bronchitis or pneumonia. Also when traveling it’s good idea to hv a supply of antibiotics on hand so u can start until u are home to see your doc. If u cough up a bit of blood go to emergency room. This happened to me. I hv had my issue for 30 yrs and only happened once. Not trying to scare you. Talk about your doctor about this. It is not very common. Drink lots of water daily. I use Symbicort daily. 2 puffs morning, 2 puffs evenings. Hope this helps! Please keep in touch! Kathy