It took about 2.5 years after I was diagnosed before they started treating my MAC. They watched it by CT and when they started seeing changes that is when they started treatment. I mainly had throat congestion, an occasional dry cough. But you have been through allot. Loosing your son and all. Personally, maybe another CT at some time to monitor the situation could be in order. Grief could also be part of your weight loss. I am very sorry that you lost your son. Bring tears to my eyes. Praying for you.