In eight (25%) of 32 consecutive AIDS patients between 1986 and 1989, Mycobacterium avium infection was diagnosed: in seven disseminated, in one as a local lymph node process. Six patients were treated as consistently as possible with a combination of ethambutol, rifabutine, clofazimine and protionamide (or cycloserine) in relatively large dosages. Median survival of treated patients was 15.5 (4-22) months. Protionamide inhibited most M. avium strains (7 of 8) in vitro, but often caused intolerance (nausea). Treatment of disseminated cytomegalovirus infection in our opinion was necessary in 5 of 6 patients during longterm M. avium therapy. HIV therapy (Zidovudine) during M. avium treatment was not possible due to bone marrow depression. A low maintenance dose of corticosteroids was necessary in 3 of 6 patients (one with adrenal insufficiency) to suppress symptoms such as fever and malaise.