What is tuberculosis?

Tuberculosis

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.

What are the symptoms of tuberculosis (TB)?

If you have latent TB, you won't have symptoms. If the disease becomes active TB, you will most likely have symptoms.

Symptoms of active TB in the lungs include:

  • A cough with thick, cloudy, and sometimes bloody mucus from the lungs (sputum) for more than 2 weeks.
  • Fever, chills, and night sweats.
  • Fatigue and weakness.
  • A rapid heartbeat.
  • Loss of appetite and losing weight without trying.
  • Shortness of breath and chest pain.

These symptoms start gradually and develop over weeks or months. You may have one or two mild symptoms and not know that you have the disease.

Symptoms of TB outside the lungs vary widely, depending on which part of the body is infected. For example, back pain can be a symptom of TB in the spine. Or your neck may get swollen when lymph nodes in the neck are infected.

Other conditions with symptoms similar to TB include pneumonia and lung cancer.

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 is tuberculosis (TB) treated?

TB is treated with antibiotics to kill the TB bacteria. These medicines are given to everyone who has TB. This includes infants, children, and people who have a weakened immune system. These medicines can also be given during pregnancy.

TB can only be cured if you take all the doses of your medicine. If you miss doses, or if you stop taking your medicine too soon, your treatment may not work. Or it may have to go on longer.

A health professional may watch you take your medicine. This is called directly observed therapy (DOT). DOT is done to help make sure that you don't miss a dose and that all the bacteria are killed.

Surgery is rarely used to treat TB. But it may be used in severe or drug-resistant TB.

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

The first phase of treatment for active TB lasts 2 months. During this phase, you take several different medicines. The second phase of treatment can last 4 to 7 months or longer. During this phase, the number of medicines you take may be reduced.

How can you care for your child who has tuberculosis (active TB)?

  • Give your child antibiotics as directed. Do not stop using them just because your child feels better. Your child needs to take the full course of antibiotics.
  • Give the medicines with food to help avoid an upset stomach.
  • Teach your child to cover their mouth for a sneeze or cough. After coughs, throw the tissue away in a covered container.
  • Keep your child away from public areas such as buses, subways, and other closed areas until you have been told that your child cannot spread TB.
  • If your child is over age 2 and is around other people, have your child wear a mask.
  • If your child doesn't have DOT, you can do things to remind yourself to give the medicines to your child.
    • Give the medicines 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 give the medicine.

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.

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