I. Epidemiology
- Disseminated MAC infection: 40% of North American AIDS
- Most common reported HIV bacterial infection
- Normal Children may develop Lymphadenitis
- Occurs under age 5 years
- Rarely affects children over age 12 years
II. Pathophysiology
- MAC is ubiquitous in environment (water, soil, food)
- Causes Tuberculosis in birds and swine
- Colonization by respiratory and gastrointestinal tracts
- Rarely occurs if CD4 Count >50
- Infection in normal children
- Breaks in mucus membrane
- Tooth Eruption
III. Symptoms
- Fever
- Fatigue
- Night Sweats
- Wasting
- Gastrointestinal upset
IV. Signs: Normal Children with Lymphadenitis
- Chronic unilateral, firm or fluctuant masses
V. Labs
- Alkaline Phosphatase increased
- Hemoglobin or Hematocrit consistent with Anemia
- Culture
- Blood Culture
- Bone Marrow Aspirate
- Lymph node biopsy
- Culture Sites not useful (may represent colonization)
-
Tuberculin Skin Testing
- Negative in 50% normal hosts (without Tuberculosis)
VI. Prevention: Prophylaxis in HIV when CD4 Count < 100
- Indicated for CD4 Cell Count < 100
- First-line prophylaxis
- Azithromycin 1200 mg PO each week
- More effective than Rifabutin
- Azithromycin 1200 mg PO each week
- Other prophylaxis options
- Combination protocol
- Azithromycin weekly and
- Rifabutin daily
- Rifabutin 300 mg/day
- Clarithromycin 500 mg PO bid
- Decreases MAC infection by 68%
- Produces survival benefit
- Combination protocol
VII. Management: MAC in HIV
- Colonization without bacteremia
- Should not be treated
- May be candidates for prophylaxis
- Treatment
- Clarithromycin and 1-2 other active agents
- Prevents resistance
- Continue drugs for the lifetime of the patient
- Clarithromycin and 1-2 other active agents
