@sueinmn I’m not sure if my pulmonologist has experience with refractive MAC. I had my first infection in 2012. Was treated with the Big 3 for 16 months. Apparently came back about 6 years ago but not confirmed or treated, cavitation and MAC confirmed in 2024. The cavitation is 3 cm and has not increased in size. My infectious disease doctor and pulmonologist both specialize in bronchiectasis and MAC treatment, thanks for your questions.