Table 2.

Summary of antibiotic regimens prescribed to patients treated for pulmonary disease associated with Mycobacterium avium complex (n = 411) and Mycobacterium abscessus (n = 76)

	Regimens for MAC (n = 579)	Regimens for M. abscessus* (n = 101)
Treatment Regimen	n (% of All Regimens)	n (% of All Regimens)
Treatment regimens meeting ATS/IDSA guidelines for MAC*	77 (13)	7 (7)
Macrolide, ethambutol, and rifamycin	75 (13)	7 (7)
Macrolide, ethambutol, rifamycin, and parenteral aminoglycoside	2 (0.3)	—
Treatment regimens not meeting ATS/IDSA guidelines for MAC*	502 (87)	94 (93)
Regimens that may increase macrolide resistance	174 (30)	18 (18)
Macrolide monotherapy	93 (16)	10 (10)
Macrolide plus fluoroquinolone	7 (1)	1 (1)
Macrolide plus rifampin	74 (13)	7 (7)
Regiments of unknown clinical significance	3 (0.5)	11 (11)
Macrolide plus inhaled amikacin	1 (0.2)	6 (6)
Macrolide plus linezolid	2 (0.3)	4 (4)
Macrolide plus parenteral aminoglycoside without ethambutol and with or without other drugs	—	1 (1)
Regimens that do not include macrolides	325 (56)	65 (64)
Ethambutol plus rifamycin	117 (20)	8 (8)
Fluoroquinolone based regimen	94 (16)	15 (15)
Parenteral aminoglycoside based regimen	15 (3)	15 (15)
Linezolid based regimen	1 (0.2)	1 (1)
Any nonmacrolide antibiotic monotherapy regimen	98 (17)	26 (26)

Definition of abbreviations: ATS = American Thoracic Society; IDSA = Infectious Diseases Society of America; MAC = Mycobacterium avium complex.

Macrolides include clarithromycin and azithromycin; rifamycins include rifampin and rifabutin; parenteral aminoglycosides include streptomycin and amikacin; and fluorquinolones include ofloxacin, ciprofloxacin, levofloxacin, and moxifloxacin. Data presented in this table refer to the total number of regimens prescribed; patients may have received more than one regimen.

^*There are currently no drug regimens of proven efficacy for the treatment of M. abscessus lung disease according to the 2007 ATS/IDSA guidelines (6).