Tuberculosis

Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but can also affect other parts of the body such as the spine, brain, or kidneys. It is spread from person to person through the air when someone with TB of the lung or throat coughs or sneezes. People nearby may breathe the TB bacteria into their lungs and become infected.

Frequently Asked Questions About Tuberculosis

1. Who gets TB?
Anyone can get TB, but some people may be at higher risk. These include close household contacts, friends, co-workers who share the same breathing space, homeless people, foreign born people coming from a country with high incidence of TB, nursing home residents, alcoholics and intravenous drug users, prisoners, people with medical conditions such as diabetes, certain cancers, and HIV.

2. What is the difference between latent TB infection and TB disease?
Latent TB infection results when the TB bacteria live in your body without making you sick. The bacteria lie inactive because the body is able to fight the bacteria to stop them from growing. These people have no symptoms and can’t spread the disease to others. TB disease can result if the bacteria become active when the immune system can’t stop them from growing. Some people develop TB disease soon after infection while others may get sick later as their immune system becomes weak for some reason.

3. What are symptoms of TB disease?
General symptoms may include fatigue, weakness, weight loss, fever and/or night sweats. TB of the lungs may cause a cough that lasts longer than 2 weeks, chest pain, coughing up blood. Other symptoms depend on which other part of the body the TB bacteria may be growing.

4. How do I know if I have latent TB infection?
First, a TB skin test is performed. If it is positive, other tests will be performed such as a chest x-ray or sputum sample to see if the person has TB disease. If it is negative it usually means that the person is not infected. However, the test can be falsely negative in the first 2 to 10 weeks after a person has been exposed and so repeat testing may be recommended. The test may also be negative in a patient with a weakened immune system so your health professional will need to carefully interpret the result for you.

5. Where can I get a TB skin test?
TB skin tests can be performed at your doctor’s office or local health department. A small needle is used to inject testing fluid called tuberculin (purified protein derivative or PPD) just under the skin on the lower part of your arm. After 2 to 3 days the reaction to the test is measured and the result will be classified as positive or negative.

6. What should I do if I have latent TB infection?
If you have latent TB infection you may need treatment to prevent you from developing active TB disease at a later time. The medicine most commonly used is called isoniazid or INH. Most people need to take this medicine for 9 months. Very few people have serious side effects from INH, but you need to contact your health care provider if you have any decreased appetite, nausea, vomiting, yellow skin or eyes, fever, abdominal pain, or tingling in the fingers or toes. It is important that you take all of your medicine as prescribed so that treatment is effective. If this medication is not tolerated, an alternative medication called rifampin can be used. Further side effects of this medication can be found below.

7. How is TB disease treated?
If you have TB disease you will need several medications to eradicate the disease. The most common drugs used to treat TB are isoniazid (INH), rifampin, pyrazinamide, and ethambutol. Treatment with several drugs will do a better job of killing all the bacteria and help to prevent them from developing resistance to the drugs. Medicine for TB is relatively safe but certain side effects can occur. Rifampin can turn urine, tears, and saliva an orange color so you need to avoid wearing soft contact lenses to prevent staining. Also, sunscreen should be worn because rifampin can make your skin more sensitive to the sun. More serious side effects of the medications used include nausea, vomiting, abdominal pain, fever, yellowing or skin or eyes, skin rash, easy bleeding or bruising, achy joints, tingling or numbness around the mouth or extremities, change in vision, and hearing loss Any of these side effects should be reported to your health care provider immediately. Treatment duration may vary depending on the location and extent of your disease, but generally the disease is treated with 6 months or more of therapy.

8. How can I keep from spreading TB?
If you have active TB disease of the lung or throat you are probably contagious and will need to stay home from work or school to prevent spreading TB bacteria to others. Your health care provider will let you know when it is safe to return to work or school after you take your medicine regularly for a few weeks. It is important that you take all of your medicine as prescribed and follow up regularly as you may need another sputum sample or chest x-ray to evaluate how well the medicine is working. If you are infectious while you are at home, certain precautions can be taken to limit the spread of disease further. Cover your mouth with a tissue when you cough, sneeze, or laugh. Avoid close contact by sleeping in a separate bedroom and air out your room frequently. TB is spread through the air in close spaces, and so cannot be spread by handshakes, sharing dishes or utensils, or sitting on toilet seats. Your local health department will evaluate the need to perform skin tests on your close contacts to ensure that they are properly treated if exposed.

9. What if I have HIV infection?
People with latent TB infection and HIV are at high risk of developing active TB disease because HIV infection weakens the immune system. All HIV infected people should be given a TB skin test to find out if they have latent TB infection . In general, latent TB infection and TB disease is treated similarly in patients with HIV, but the potential for drug interactions with HIV medications may complicate therapy.