Mycobacterium Avium Complex - Causes, Symptoms and Treatments

Mycobacterium Avium Complex Definition

A genus of aerobic, nonmotile bacteria containing gram-positive rods and including both parasitic and saprophytic species. Mycobacterium avium complex (MAC) consists of several related species of mycobacterium that are ubiquitous in the environment. Mycobacterium avium complex organisms can be found virtually anywhere in the environment.

Mycobacterium avium complex is usually found in people with CD4 counts below 100. Any organ system can he involved, especially those with many mononuclear phagoeytes. Less commonly, Mycobacterium avium complex may produce pulmonary disease in nonimmunocompromised people; it may manifest in children as cervical lymphadenitis.

Mycobacterium Avium Complex Causes

An opportunistic infection, that may be caused by two similar slow-growing bacteria called Mycobacterium avium and Mycobacterium intercellulare. Mycobacterium avium and Mycobacterium intercellulare may be found in the soil and in dust particles. Disseminated Mycobacterium avium complex infections are usually associated with immunocompromise, as in AIDS. Mycobacterium avium complex most often causes a disseminated illness (bacteria is spread though the blood stream) and can cause many symptoms throughout the body.

Mycobacterium avium complex can be spread through the bloodstream to infect lymph nodes, bone marrow, liver, spleen, spinal fluid, lungs and intestinal tract. It is impossible to avoid contact with Mycobacterium avium complex bacteria. A recent study showed that person-to-person transmission of MAC bacteria is unlikely.

Mycobacterium Avium Complex Symptoms

MAC can infect a person's entire body. The signs and symptoms of mycobacterium avium complex are generally nonspecific. The signs and symptoms of mycobacterium avium complex can be the same signs of other diseases.

The symptoms of the mycobacterium avium complex may be included:

• Anemia
• High fever
• Fatigue
• Diarrhea
• Hepatitis
• Weakness
• Neutropenia
• Skin lesions
• Pneumonia
• Night sweats
• Weight loss
• Enlarged spleen
• Drenching sweats
• Abdominal pain
• Blood infections
• Thrombocytopenia
• Elevated liver function tests

Mycobacterium Avium Complex Treatments

Treatment usually involves taking several drugs for a long time.

You should not get treatment to prevent MAC disease until your T-cell count is below 50. Your doctor will tell you when you or your child need to begin treatment for preventing MAC disease.

The addition of rifabutin (300 mg daily) has been associated with increased mycobacterial clearance, but no survival benefit.

Health care providers use a combination of antibacterial drugs (antibiotics) to treat MAC. At least two drugs are used: usually azithromycin or clarithromycin plus up to three other drugs.