Tuberculosis

Diagnosis

To diagnose a tuberculosis (TB) infection, your healthcare professional will do an exam that includes:
• Listening to you breathe with a stethoscope
• Checking for swollen lymph nodes
• Asking questions about your symptoms

TB tests

Your healthcare professional will order tests if:
• Tuberculosis is suspected
• You were likely exposed to someone with active TB disease
• You have health risks for active TB disease

Your healthcare team will decide whether a skin test or blood test is the most suitable option.

Skin test

A small amount of a substance called tuberculin is injected just under the skin on the inside of one forearm. Within 48 to 72 hours, a healthcare worker checks your arm for swelling at the injection site. The size of the raised area helps determine whether the test is positive or negative.

This test looks for an immune response, meaning your immune system has reacted to tuberculosis. A positive test suggests a latent TB infection or active TB disease. People who received a TB vaccine may test positive even without an infection.

A negative result means there was no reaction, but it does not completely rule out infection.

Blood tests

A blood sample is sent to a lab. One type of test checks whether certain immune system cells recognize tuberculosis. A positive result shows you likely have a latent TB infection or active TB disease. Additional tests on the same blood sample can help determine if active disease is present.

A negative test generally means you likely do not have a TB infection.

X-ray

A chest X-ray can reveal irregular patches in the lungs that are typical of active TB disease.

Sputum tests

Your healthcare professional may collect a sample of the mucus you cough up, known as sputum. If you have active TB disease in your lungs or voice box, lab tests can detect TB bacteria.

A quick test may indicate whether the sputum likely contains TB bacteria, though it may detect bacteria with similar features. Another lab test can confirm the presence of TB bacteria, but results can take several weeks. Testing also helps identify drug-resistant forms of TB, which guides treatment decisions.

Other lab tests

Additional tests that may be ordered include:
• Breath test
• Procedure using a special tube to remove sputum from the lungs
• Urine test
• Test of cerebrospinal fluid, the fluid around the brain and spine

Treatment

If you have a latent TB infection, your healthcare professional may start treatment, especially if you have HIV/AIDS or other risk factors that increase the chance of developing active TB disease. Most latent TB infections are treated for three or four months.

Active TB disease may be treated for four, six, or nine months. TB specialists determine which medicines are appropriate for your condition.

You will have regular appointments to monitor improvement and watch for side effects.

Take all of the medicines

It is important to take every dose exactly as instructed. Completing the full course of treatment is essential to kill the bacteria and prevent drug resistance.

Your public health department may use a program called directly observed therapy, or DOT. With DOT, a healthcare worker visits you at home to watch you take your medicines.

Some health departments allow you to take your medicines on your own. The Centers for Disease Control and Prevention offers printable forms to help track daily doses.

Most common TB medicines

If you have a latent TB infection, you may need one or two medicines. Active TB disease typically requires several medicines. Common TB treatments include:
• Isoniazid
• Rifampin
• Rifabutin
• Rifapentine
• Pyrazinamide
• Ethambutol

Other medicines may be used if you have drug-resistant TB or complications from the illness.

Medication side effects

Most people take TB medicines without serious problems. If you develop serious side effects, your healthcare professional may ask you to stop or adjust a medicine.

Contact your healthcare professional if you experience:
• Upset stomach
• Vomiting
• Loss of appetite
• Severe diarrhea
• Light-colored stool
• Dark urine
• Yellowish skin or eyes
• Changes in vision
• Dizziness or balance problems
• Tingling in hands or feet
• Easy bruising or bleeding
• Unexplained weight loss
• Unusual tiredness
• Sadness or depression
• Rash
• Joint pain

Make sure to list all medicines, supplements, and herbal products you take. Some may need to be stopped during treatment.