Sunday, July 29, 2007

What is Mycobaterium Avium Complex (MAC)?

Mycobacterium is a type particularly strong organism that has been known to cause tuberculosis leprosy and Mycobacterium avium complex (MAC). There are two main classifications of Mycobaterium: fast-growing and slow-growing. Mycobaterium are primarily found in water and food. Even water that has been disinfected with chlorine can still harbor a member of the Mycobacterium family. There are strains of non-tuberculosis mycobacterium (NTM) that are generally referred to as “TB cousins.”

How Prevalent is It?

People with cystic fibrosis are more susceptible to infection than their healthy peers. According to a study published in 2002 in the American Journal of Respiratory and Critical Care, Mycobacterium Avium Complex (MAC) was cultured in over 70% of the test subjects.

Causes and Symptoms

Avoiding contact with some source of MAC is virtually impossible. Animal, water, air, food, soil, tobacco products are all suspected vectors for the mycobacterium avium complex. Unlike B. Cepapcia complex, Staph Aureus, Psuedomanas Aeruginosa, or other infectious conditions common in the cystic fibrosis community, MAC is not spread through person-to-person contact. This The most common TB Cousin, MAC, presents itself like many other illnesses. Without a the conclusive results from a sputum sample, MAC may be misdiagnosed as just another pulmonary exacerbation, or the flu. Common symptoms of infection include:

  • Fever
  • Chills
  • Swollen glands
  • Nigh sweats
  • Fatigue

How it is Diagnosed

MAC is diagnosed by drawing blood to determine the function of the liver. This is because the condition causes the number of liver enzymes to be elevated. A sputum culture is also necessary for detecting the presence of MAC.


Treating MAC is difficult, especially becaue it typically requires dual antibiotic therapy. Medical professionals agree that Azithromycin should be one of the drugs used. However, this can be challenging, especially for CF patients who are already taking a prophylactic dose of azithromycin. Unfortunately, MAC cannot be eradicated by the usual 10 day course of antibiotics. Treatment for the condition is ongoing and life-long.

MAC fact sheet

Multicenter Prevalence Study in CF

No comments: