To determine the safety and efficacy of azithromycin, rifabutin and ethambutol given three times weekly in the treatment of lung infection with M. avium complex(MAC)

Azithromycin given 3 times weekly along with rifampin/rifabutin and ethambutol for treatment of MAC

Inclusion Criteria:

• Meet American Thoracic Society criteria for nontuberculous lung disease: two or more AFB smear positive, culture positive sputums or bronchoscopic samples and/or two or more AFB smear negative respiratory samples with moderate to heavy growth (2+-4+); abnormal CXR consistent with M. avium lung disease; abnormal CXR consistent with M. avium lung disease; absence of other lung pathogens (except for the coexistence of M. abscessus).
• Age 18 and older
• Pretreatment isolate of M. avium complex available for MIC determination
• Baseline laboratory and clinical testing for baseline CBC, Chemistry (including liver enzymes), hearing test, visual acuity and color discrimination
• Available for long term followup

Exclusion Criteria:

• History of macrolide or rifamycins allergy
• Laboratory evidence of mycobacterial resistance to azithromycin
• Children less than 18 years of age
• If a menstruating female, not pregnant and on adequate birth control
• HIV+ or at risk