Mycobacterium avium complex infection

Overview

Infection with an opportunistic group of bacteria. It tends to occur in immunocompromised people such as those with HIV.

Symptoms

* Fever * Weight loss * Chills * Night sweats * Swollen glands * Abdominal pains * Diarrhea * Overall weakness * Fatigue * Anemia

Diagnosis

Diagnosis can be achieved through blood cultures, or cultures of other bodily fluids such as sputum. Bone marrow culture can often yield an earlier diagnosis, but is usually avoided as an initial diagnostic step because of its invasiveness.

Treatment

Because antimicrobial resistance develops quickly with single-drug therapy, multidrug regimens must be administered for DMAC. The U.S. Centers for Disease Control and Prevention recommends the following 2-drug regimens: * Clarithromycin 500 mg twice daily + ethambutol 15 mg/kg once daily * Azithromycin 500-600 mg once daily + ethambutol 15 mg/kg once daily Some experts recommend including a third agent for more advanced disease or for patients not taking effective ART. The addition of rifabutin (300 mg daily) has been associated with increased mycobacterial clearance, but no survival benefit. A fluoroquinolone (eg, ciprofloxacin, levofloxacin) or amikacin may be used instead of rifabutin as a third agent, or in addition to rifabutin as a fourth agent; however, studies have not confirmed the clinical benefit of these medications. Treatment of MAC is generally required for the remainder of the patient's life, although it may be reasonable to discontinue MAC therapy if patients complete at least 12 months of MAC treatment, have no further symptoms, and demonstrate immune restoration in response to ART (an increase in CD4 counts to >100 cells/µL for at least 6 months). If MAC treatment is discontinued, the patient must be monitored carefully for any decrease in CD4 cell count or recurrence of MAC symptoms. Some clinicians verify negative AFB cultures before discontinuing therapy. Treatment should be resumed if the CD4 count drops to