What are the diagnostic tests for tuberculosis?

What are the diagnostic tests for tuberculosis?

There are two kinds of tests that are used to detect TB bacteria in the body: the TB skin test (TST) and TB blood tests. A positive TB skin test or TB blood test only tells that a person has been infected with TB bacteria.

How is pulmonary tuberculosis diagnosed?

To diagnose pulmonary TB specifically, a doctor will ask a person to perform a strong cough and produce sputum up to three separate times. The doctor will send the samples to a laboratory. At the lab, a technician will examine the sputum under a microscope to identify TB bacteria.

How is sputum TB diagnosed?

Test Overview One of the best ways to diagnose TB is through a sputum culture. A sputum culture is a test to find germs (such as TB bacteria) that can cause an infection. A sample of sputum is added to a substance that promotes the growth of bacteria. If no bacteria grow, the culture is negative.

What is the most sensitive test for tuberculosis?

If sputum smears and NAA tests are negative, and TB is still suspected, cultures are the most sensitive tests for TB. Culture is therefore very useful for diagnosing both smear-negative TB and drug-resistant TB.

What is sputum AFB test?

AFB smear—a microscopic examination of a person’s sputum or other specimen that is stained to detect acid-fast bacteria. It is a rapid test used to provide presumptive results within one to two days. It is valuable in helping to make decisions about treatment while waiting for culture results.

How do you test for TB without sputum?

If a patient with presumed pulmonary tuberculosis cannot cough up sputum, there are other ways to get body fluids that contain Mycobacterium tuberculosis. Health workers can do gastric washings, a so-called laryngeal swap or get a sample through a bronchoscopy.

What is positive TB test?

A “positive” TB blood test result means you probably have TB germs in your body. Most people with a positive TB blood test have latent TB infection. To be sure, your doctor will examine you and do a chest x-ray. You may need other tests to see if you have latent TB infection or active TB disease.