Is there a role for dual antibiotic treatment with ethambutol and macrolide only, as opposed to three-drug antibiotic therapy, in the treatment of treatment-naive pulmonary MAC without cavitary disease?  

That is a great question, as the role of rifampin (or rifabutin) regarding its relative contribution to the treatment of MAC is not overly clear. Historic data that is a few decades old raised the possibility of better activity when a rifamycin is combined with ethambutol (at least in vitro and furt...

That is REALLY helpful, Dr. @Wilson! When I was in training (1994 era), we saw lots of MAI bacteremia in AIDS patients, and the standard approach was to use 2 drugs: macrolide + Ethambutol. To my memory, I believe there was some data showing that the addition of Rifabutin really did not have benefi...