Mycobacterial infections


A large group of bacteria, called mycobacteria, can cause infections in humans. These bacteria have waxy cell walls that help protect them against attacks and digestion. As a result, the unique outer coating of mycobacteria makes them difficult to destroy.
The most common types of mycobacterial infections include tuberculosis, leprosy, and mycobacterium avium complex.
Tuberculosis (TB) is a bacterial infection of the lungs that is caused by the microorganism Mycobacterium tuberculosis. Tuberculosis is transmitted through airborne droplets of infected mucus or phlegm (called sputum). Individuals can have the bacteria in their bodies without actually being infected or experiencing symptoms. This is called a latent TB infection. Individuals who have latent TB infections have healthy immune systems that are able to suppress the infection. Patients with latent TB do not require any medical treatment. Only 10% of individuals with latent TB ever develop the infection.
Leprosy is an infectious disease that is characterized by disfiguring skin sores and nerve damage. A mycobacterium, called Mycobacterium leprae, causes leprosy. This bacterium is present in the soil and on some armadillos.
There are two types of leprosy: tuberculoid and lepromatous. Both forms cause skin sores and nerve damage that leads to decreased sensations. However, lepromatous is more severe. Researchers believe that the lepromatous form is contagious and may be transmitted from person to person. The tuberculoid form is not contagious.
Mycobacterium avium complex (MAC) is a bacterial infection that is caused by either Mycobacterium avium or Mycobacterium intracellulare. MAC infections are classified under a subgroup of mycobacteria called nontuberculous mycobacteria (NTM). Because the bacteria that cause MAC are found almost everywhere in the environment, they are present in almost all humans. However, an infection only develops if the person has a weakened immune system. This type of infection is most common in HIV/AIDS patients.
Mycobacterial infections can be successfully treated with antibiotics. However, if left untreated, mycobacterial infections may spread to vital organs and become life threatening. Therefore, individuals should visit their healthcare providers to diagnose and treat an infection as soon as symptoms develop.

Related Terms

Active tuberculosis, antibiotics, bacteria, bacterial infection, bacterium, clofazimine, dapsone, DMAC, HIV, immune response, immune system, immunocompromised, infection, latent TB, latent tuberculosis, leper, lepromatous, lepromatous leprosy, lepromin skin test, MAC, MDT, multidrug therapy, Mycobacterium leprae, nerve damage, nodules, peripheral nerve damage, peripheral nerves, tuberculoid, tuberculoid leprosy, reconstructive surgery, rifampin, TB, tuberculosis, weakened immune system.