Tuberculosis (TB) is one of the most common infections in the world. It is less common in the United States than developing regions such as Africa, India and South America. Nonetheless, TB is an important public health issue because it is very contagious. The infection is caused by the organism Mycobacterium tuberculosis. When the organism is inhaled, it first gets trapped in the lung. Most peoples' bodies are able to wall the infection off within the lung. In the majority of people the infection will remain dormant for the rest of a person's life (Latent TB). However, in some people, particularly children and infants, people with weakened immune systems or people recently infected with TB, the infection may spread and cause a pneumonia (Active TB). During this phase of the illness, the mycobacterium is very contagious. Coughing spreads the organisms. People in close contact are at particular risk for acquiring TB.
Latent TB is asymptomatic and there is no risk of spreading the infection. However, active TB is very infectious. In some people, TB will spread outside of the lungs into bones, kidneys or other tissues in the body. Unlike active lung infection, TB that is active outside of the lungs is not contagious.
Symptoms of active pulmonary TB include fever, night sweats, weight loss and importantly cough. The disease is diagnosed by collecting sputum specimens. Chest X-rays may be helpful in suggesting the diagnosis, but a firm diagnosis requires confirmation by culture. Sputum specimens are often collected on several occasions to increase the likelihood of making a diagnosis. The cultures can take up to eight weeks.
Treatment of active TB involves multiple medications taken for many months. A typical course would involve 4 medications for two months followed by 2 medications for 4 months. However, TB can be resistant to our usual medications. Under these conditions, other medications are used and may be continued for longer. All cases of active TB must be reported to the public health department. In some cases, the department of public health will require you to come in and take your medications at their offices. Without proper treatment TB can be a life-threatening infection. Furthermore, without appropriate treatment, the infection can spread to your friends and family members and anyone in close contact with you.
Treatment of latent TB may be offered under certain circumstances. The usual regimen is the drug Isoniazid, which is taken for six to nine months.
The lung and infectious disease doctors at Arizona Pulmonary Specialists are experts in the diagnosis and treatment of TB. Our team of doctors, nurses and respiratory therapists will work with you to ensure that you understand your medications and other treatments.