@garry - This is a truly frustrating disease, and answers can be hard to get.
Here is what I have learned since diagnosis about 2 years ago:
It is very important to find a pulmonologist well-versed in MAC and one who keeps up-to-date in treatment options. No easy task if you are not in a populous area. My Primary referred me immediately when bronch was suspected because there are so many variables. I switched pulmonologists when I realized the first one wasn't willing to consider any but the most basic forms of treatment.
Most people don't know "how I got it", but there are a lot of known vectors to avoid. Hot tubs and steam rooms top the list. Also, steamy showers, garden & potting soil, humidifiers and water filters, in some cases our very water supply... We all need to protect ourselves as best we can. So I have given up the community hot tub, limit my showers, wear mask & gloves for handling soil, pay someone to do the dusty yard work. But I haven't had my water tested because I believe the digestive tract kills MAC and don't have any kind of reflux. Others with reflux issues choose to be more cautious, boiling the water they use for cooking, drinking & cleaning their equipment.
Everyone responds differently to the medication. In my case it caused severe digestive issues, fatigue & weight loss, which I tolerated until the CT scan showed the lesions on my lungs were disappearing and my cough was gone. The infectious disease doc stopped it after 1 1/2 years to give my body a break. I still test positive in my sputum, but we are trying a 7% saline neb to eradicate it. At some point, if the saline isn't effective and the cough & spots come back, I'll probably be back on the meds.
If your doctor is considering treatment again, it is vital that sensitivity testing be done on you sputum culture so that the correct drugs are used, my understanding is that, except for maintenance (see @windwalker) single meds are not effective.
Sorry for the long post, but I am passionate about helping people advocate for themselves and get the answers they need.
By the way, there ARE people studying MAC! And it is an evolving knowledge base. National Jewish Health is a wonderful source of information, here is a link: https://www.nationaljewish.org/education/pro-ed/live-events/ntm-patient-videos.
Has your sputum been tested recently to be sure you are on the best regimen for what you have? There are many strains of MAC, and you may have a different one than the original, or the one you have may have become resistant to the antibiotic you have used for a long time.
Sue

@garry Sorry to tell you, but it kind of does! I never had a radiologist call me at home till we moved to Tennessee for a hot second. This Dr. called me and told me to get right to my primary for further evaluation as there was something very suspicious on my X-ray. (Which was taken for a back issue). I calmed the poor man down and told him “No worries, I have nodular MAC, and my doctor is well aware.” I was actually touched by the fact he was so concerned and had called me! So I guess it kind of shows up as “something.” A CT scan will confirm MAC.