with gradual introduction of therapy within a short
time period; this approach may improve compliance and adherence to treatment.
After determining that the patient requires therapy and whether suppressive or aggressive therapy should be initiated, the standard recommended
treatment for MAC pulmonary disease includes the
following: 9 For most patients with nodular/bron-chiectatic disease, a thrice-weekly regimen of clarithromycin (1000 mg) or azithromycin (500 mg),
rifampin (600 mg), and ethambutol (25 mg/kg)
is recommended. For patients with fibrocavitary
MAC pulmonary disease or severe nodular/bron-chiectatic disease, a daily regimen of clarithromycin (500–1000 mg) or azithromycin (250 mg),
rifampin (600 mg) or rifabutin (150– 300 mg), and
ethambutol ( 15 mg/kg), with consideration of 3
times/week amikacin or streptomycin early in
therapy, is recommended. Treatment of disseminated MAC disease should include clarithromycin
(1000 mg/day) or azithromycin (250 mg/day)
and ethambutol ( 15 mg/kg/day) with or without rifabutin (150–350 mg/day). The duration of therapy depends upon resolution of signs and immune
Prophylaxis for disseminated MAC disease should
be given to HIV-infected adults with a CD4+ count
less than 50 cells/μL. Azithromycin 1200 mg/week
or clarithromycin 1000 mg/day have proven efficacy, and rifabutin 300 mg/day is also effective
but less well tolerated. Rifabutin is more active in
vitro than rifampin against MAC and is used in HIV-positive patients because of drug-drug interaction
between antiretroviral drugs and rifampin.
For MAC hypersensitivity pneumonitis, avoidance of exposure is the mainstay of management.
In some cases, steroids are used with or without a
short course of anti-MAC therapy (ie, clarithromy-cin/azithromycin, rifampin, ethambutol).
CASE 2 CONTINUED
The patient is treated with clarithromycin,
rifampin, and ethambutol for 1 year with
sputum conversion after 9 months. In the later part
of her treatment, she experiences decreased visual
acuity. Treatment is discontinued prematurely after
1 year due to drug toxicity and continued intolerance to drug therapy. She remains asymptomatic
for 8 months and then begins to experience mild
to moderate hemoptysis with increasing cough
and sputum production associated with postural
changes during exercise. Physical examination
overall remains unchanged. Three sputum results
reveal heavy growth of MAC, and a CT scan of the
chest shows a cavitary lesion in the left upper lobe
along with the nodular bronchiectasis (Figure 5).
• What;are;the;management;options at;this
Based on this patient’s continued symptoms,
progression of radiologic abnormalities, and current culture growth, she requires retreatment. With
Figure 5. Computed tomography of the chest demonstrating a
cavitary lesion and nodular bronchiectasis in the left upper lobe.