TABLE 1
Diagnostic Criteria for Mycobacterium avium
complex Pulmonary Disease
The following criteria apply to symptomatic patients with infiltrate, nodular or cavitary disease, or a high resolution computed
tomography scan that shows multifocal bronchiectasis and/or multiple small nodules.
A. If three sputum/bronchial wash results are available from the previous 12 mo:
1. three positive cultures for MAC with negative AFB smear results or
2. two positive cultures for MAC and one positive AFB smear
B. If only one bronchial wash is available:
1. positive culture with a 2+, 3+, or 4+AFB smear or 2+,3+, or 4+
growth of MAC on solid media
C. If sputum/bronchial wash evaluations are nondiagnostic or another disease cannot be excluded:
1. transbronchial or lung biopsy yielding MAC or
2. biopsy showing mycobacterial histopathologic features
(granulomatous inflammation and/or AFB) and one or
more sputums or bronchial washings are positive for MAC even in low numbers
At least three respiratory samples should be evaluated from each patient. Other reasonable causes for the disease should be excluded. Expert consultation should be sought when diagnostic difficulties are encountered.
TABLE 2
Treatment and Prophylaxis of AIDS associated
Mycobacterium avium complex disease
| Preferred Therapy | Alternate Therapy | Duration | Special Considerations | |
| Initial therapy (at least two drugs) | Clarithromycin 500 mg PO BID + Ethambutol 15 mg/kg PO QD | Alternative to Clarithromycin Azithromycin 500 - 600 mg PO QD | Chronic Maintenance Therapy should be continued lifelong, unless there is a sustained immune response with ARV | Symptomatic assessment should demonstrate improvement in 4 - 6 weeks. If failure is suspected, repeat blood cultures. Consider evaluating sensitivity to macrolides if cultures are positive. |
| Third Agent | Rifabutin 300 mg PO QD ( dose adjust based on drug interactions as necessary) Consider adding third agent if ARV is not initiated, or evidence of high mycobacterial loads | Alternative third or fourth agent for patients with severe symptoms or disseminated disease Ciprofloxacin 500-750 mg PO BID; or Levofloxacin 500 mg PO QD; or Amikacin 10 - 15 mg/kg IV QD | NSAIDs may be used for patients who experience moderate to sever symptoms attributed to ARV - associated immune reconstitution syndrome. If symptoms of IRIS persist, a short term ( 4 – 8 week ) course of systemic corticosteroid ( prednisone QD 20 - 40 mg PO QD) can be used. | |
| Chronic Maintenance Therapy (secondary prophylaxis) | Clarithromycin 500 mg PO BID + Ethambutol 15 mg/kg PO QD with or without rifabutin 300 mg PO QD | Azithromycin 500 mg PO BID + Ethambutol 15 mg/kg PO QD with or without rifabutin 300 mg PO QD | Maintenance therapy can be discontinued in patients who complete at least 12 months of therapy, remain asymptomatic and have sustained CD4 count > 100 cells/mm3 for at least 6 months | |
| Primary Prophylaxis | Azithromycin 1200 mg PO q week or Clarithromycin 1000 mg PO QD ( extended release) or 500 mg PO BID | Rifabutin 300 mg PO QD |
TABLE 3
Treatment of Mycobacterium avium
complex Pulmonary Disease
|
|
Preferred Therapy |
Alternate Therapy |
Duration |
Special Considerations |
|
Initial Therapy |
Clarithromycin 500 mg PO BID + Rifabutin 300 mg PO QD + Ethambutol 25 mg/kg QD for the first 2 months followed by 15 mg/kq QD |
Alternative to Clarithromycin Azithromycin 250 mg PO QD or 500 mg PO three times a week Alternative to Rifabutin - Rifampin 600 mg PO QD |
Treatment should be continued for at least 12 months after last positive sputum culture on a macrolide containing regimen. |
Patients with small body mass or age over 70, clarithromycin 250 mg QD or azithromycin 250 mg three times a week may be better tolerated. |
|
|
|
|
|
|
|
Adjunctive Therapy |
Streptomycin 1 gm QD five times a week (based on normal creatinine clearance ) |
Ciprofloxacin 750 mg PO BID or Ofloxacin 400 mg PO BID or Ethionamide 250 mg PO BID |
Intermittent Streptomycin is recommended for only the first 2 to 3 months of treatment of extensive disease |
Patients receiving streptomycin should be instructed on the signs and symptoms of ototoxicity and vestibular toxicity( tinnitus, decreased hearing, unsteady gait). Ototoxicity due to streptomycin is often irreversible. |
TABLE 4
Antimycobacterial Agents Commonly Used in the Treatment
of MAC Infections
| Agent | Adult Dose | Adverse Effects |
| Amikacin | 7.5 - 15 mg/kg QD IV | Ototoxicity, nephrotoxicity |
| Azithromycin | 500 mg/day | Nausea, diarrhea, vomiting, abdominal pain, headache, dizziness, elevated hepatic enzymes |
| Ciprofloxacin | 750 mg BID | Anorexia, nausea, vomiting, abdominal pain, diarrhea, rash, mental status changes |
| Clarithromycin | 500 mg BID | Diarrhea, nausea, vomiting, elevated hepatic enzymes, abdominal pain, renal insufficiency |
| Ethambutol | 15 mg/kg/day | Anorexia, nausea, vomiting, diarrhea, rash, elevated hepatic enzymes, ocular changes - retrobulbar neuritis |
| Rifabutin | 300 mg/day | Anorexia, nausea, vomiting, diarrhea, rash, uveitis, myalgias, arthralgias, headache |
| Rifampin | 10 mg /kg/day | Anorexia, nausea, vomiting, diarrhea, rash, elevated hepatic enzymes |