What is tuberculosis?


Tuberculosis (latent TB): Overview

Latent tuberculosis (TB) means that you have bacteria in your body that could cause active TB disease. You can't spread the bacteria to other people at this time. But if your immune system can't keep the bacteria from growing, the disease becomes active. People with weakened immune systems are more likely to develop active TB.

With active TB in your lungs, you can spread the disease to others. Active TB is a serious disease.

Latent TB doesn't have any symptoms. You may even be surprised that you have it, since you don't feel sick. It's very important to take your antibiotic medicine as your doctor tells you to. This treatment prevents you from getting active TB. It takes a long time to rid your body of TB. You may be taking medicine for many months. During your treatment you'll see your doctor for tests to see how the medicine is working. Your doctor will help guide you through this long process.

You may have directly observed therapy (DOT). This means that a health care worker watches when you take your medicine. DOT helps you remember to take your medicine. And it helps you complete your treatment as soon as possible.

Tuberculosis (TB)

Tuberculosis (TB) is an infection caused by bacteria. It usually affects the lungs. Symptoms may include fever, extreme fatigue, weight loss, night sweats, and a cough that brings up thick, bloody mucus.

TB can be deadly if it isn't treated.

What happens when you have tuberculosis (TB)?

TB develops when you breathe TB bacteria into your lungs. The infection usually stays in the lungs. But the bacteria can travel through the bloodstream to other parts of the body. When that happens, it becomes active TB. If active TB isn't treated, it can cause respiratory damage.

What are the symptoms of active tuberculosis (TB)?

Symptoms of active TB start gradually and develop over weeks or months. You may have a cough, lose your appetite, and lose weight. You may have night sweats, a fever, or chills. And you may feel tired and weak.

How is tuberculosis (TB) treated?

TB is treated with antibiotics to kill the TB bacteria. How many antibiotics are used and how long you'll take them may depend on whether you have active or latent TB. TB can only be cured if you take all the doses of your medicine.

How can you help prevent tuberculosis (TB)?

TB in the lungs is spread very easily. To avoid getting TB:

  • Don't spend long periods of time in a stuffy, closed room with someone who has active TB until that person has been treated for at least 2 weeks.
  • Use measures to protect yourself, if you work somewhere that cares for people who have untreated TB. An example is wearing a face mask. Face masks must be certified by the CDC and National Institute for Occupational Safety and Health (NIOSH).
  • If you live with someone who has active TB, help the person follow treatment instructions.

The TB vaccine

A TB vaccine is used in parts of the world where the risk of getting TB is higher. But it's almost never used in the United States.

How is tuberculosis (TB) diagnosed?

Doctors usually find latent TB by doing a tuberculin skin test. A doctor or nurse will inject TB antigens under your skin. If you have TB bacteria in your body, within 2 days you will get a red bump where the needle went into your skin. The test can't tell when you became infected with TB or if it can be spread to others. A blood test also can be done to look for TB.

To find TB in the lungs, doctors test a sample of mucus from the lungs to look for TB bacteria. Doctors sometimes do other tests or take a chest X-ray to help find TB in the lungs.

To find TB that's not in the lungs, doctors may take a tissue sample (biopsy) or do imaging tests.

How are medicines used to treat tuberculosis (TB)?

TB is treated with antibiotics to kill the TB bacteria.

In most cases, doctors combine four antibiotics to treat active TB. You must take the medicine for active TB for at least 6 months. If tests still show an active TB infection after 6 months, then treatment lasts up to 9 months or longer. If the TB bacteria are resistant to several antibiotics (multidrug-resistant TB), then treatment may be needed for a year or longer.

If you have latent TB, you may be treated with one or more antibiotics for many months.

TB can only be cured if you take all the doses of your medicine. A doctor or nurse may watch you take it to make sure that you never miss a dose.

Who can diagnose and treat tuberculosis (TB)?

Health professionals and public health agencies can help you find out if you have tuberculosis (TB) and can help with treatment. These include:

  • Your local public health department.
  • Primary care doctors. These are general practitioners, family medicine physicians, internists, and pediatricians.
  • Pulmonologists. These are doctors who specialize in treating lung problems.
  • Infectious disease specialists.

If you have multidrug-resistant TB (MDR-TB), you may need to go to a special treatment center that treats this type of TB.

How can you care for yourself when you have tuberculosis (latent TB)?

  • Take your antibiotics as directed. You need to take the full course of antibiotics.
  • If you get an upset stomach while taking the medicine, ask your doctor if it's okay to take it with food.
  • If you forget to take your medicine, take the dose as soon as you can if it's the same day. Do not take two doses at the same time. If the day has passed, then take your next scheduled dose. Tell your doctor or public health worker that you missed a dose so your treatment schedule can be adjusted.
  • Avoid drinking alcohol. Alcohol may interact with your medicine and cause side effects.
  • If you don't have directly observed therapy (DOT), there are things you can do to help remind you to take your medicine:
    • Take your medicine at the same time every day.
    • Set a reminder alarm.
    • Use a pillbox.
    • Put a reminder note on your mirror or refrigerator.
    • Mark a calendar after you take your medicine.

Who is most at risk for tuberculosis (TB)?

Some people are more likely than others to get TB. This includes people who have a weak immune system, have close contact with someone who has active TB, have poor access to health care, or abuse drugs or alcohol. People who travel or live where untreated TB is common are also at risk.

How does tuberculosis (TB) spread?

TB that's in the lungs can spread when a person who has active TB breathes out air that has the TB bacteria in it. Another person may breathe in the bacteria. Things like coughing can also release even more bacteria. TB that isn't in the lungs can't spread easily to others.

What causes tuberculosis (TB)?

TB is caused by Mycobacterium tuberculosis. This is a type of slow-growing bacteria. It thrives in parts of the body that are rich in blood and oxygen, such as the lungs.

What other health problems can be caused by tuberculosis (TB)?

Without treatment, active TB can cause other serious health problems, such as:

  • Pockets or cavities that form in the lungs. These damaged areas may cause bleeding in the lungs or may become infected with other bacteria and form pockets of pus (abscesses).
  • A hole that forms between nearby airways in the lungs.
  • Difficulty breathing because of blocked airways.

What is tuberculosis (TB)?

Tuberculosis (TB) is a serious disease caused by a type of bacteria that is spread through the air. TB is easily spread from person to person through coughs or sneezes. TB usually occurs in the lungs. But it can spread to other parts of the body.

TB is either active or latent.

  • Active TB means that the TB bacteria are growing and causing symptoms. If your lungs are infected with active TB, it's easy to spread the disease to others.
  • Latent TB means that you have the TB bacteria in your body, but your body's defenses (immune system) are keeping it from turning into active TB. This means that you don't have any symptoms of TB right now and can't spread the disease to others. If you have latent TB, it can become active TB.

Tuberculosis (active TB): When to call

Call 911 anytime you think you may need emergency care. For example, call if:

  • You have severe trouble breathing.
  • You are coughing up a lot of blood.

Call your doctor now or seek immediate medical care if:

  • You are short of breath.
  • You have a new or worse cough.
  • You are coughing up a small amount of blood.
  • You are dizzy or lightheaded, or you feel like you may faint.
  • You have new or worse diarrhea.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You lose weight.
  • You have night sweats.
  • You do not get better as expected.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.