Mycobacterium Avium Complex

Mycobacterium avium complex (MAC) is a group of bacteria, commonly found in soil or water, that can infect people who have acquired immunodeficiency disease (AIDS). In people whose CD4+ cell count drops below 50 cells per microliter (mcL), the bacteria can spread throughout the body and cause infection almost anywhere.

Symptoms include:

  • Night sweats.
  • Fever.
  • Diarrhea.
  • Fatigue.
  • Weight loss.
  • Belly pain.

There is no easy way to avoid exposure to Mycobacterium avium complex bacteria. But medicines are available that can prevent disease.

Last Revised: April 5, 2012

Author: Healthwise Staff

Medical Review: E. Gregory Thompson, MD - Internal Medicine & Peter Shalit, MD, PhD - Internal Medicine

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