What is an AFB test? What does a positive AFB mean?

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An AFB or Acid Fast Bacilli AFB test detects the presence of the Acid-fast bacillus bacteria that is associated with causing tuberculosis and other infections. The lung infection can cause serious complications in the spine, kidneys, brain, and other parts of the body as the infection spreads throughout the body.

Importance of getting an AFB test

The key reason why it is important to get an AFB test is to detect the presence of the Mycobacterium species of infection. TB and other conditions can be latent or active, and your risk factor rises significantly.


If you have active symptoms of TB or other infections, then you may be advised to get an AFB test performed. You may undergo an AFB smear or AFB culture test which can diagnose the presence of infections in the body.



Meaning of a positive AFB test result

An Acid Fast Bacillus AFB test will be able to provide insight on whether you are currently dealing with an infection. The acid fast bacteria test positive result can indicate that you may have an active case of TB or other infections. You may have to undergo a susceptibility test as well to understand the impact of antibiotics in the body.


The timely detection of the infection can help in faster treatment initiation. This can help you prevent the complications that can emerge from TB and prevent the spreading of the infection from person to person.

Chief symptoms of tuberculosis

There are several symptoms of tuberculosis that you should be aware of, so that you can get the AFB smear and culture test done as soon as possible. The test for AFB can help you understand whether your symptoms are related to tuberculosis or other infections.

Severe coughing fits

A key symptom of tuberculosis is coughing fits that can last for upwards of 4 weeks. If you have been experiencing coughing fits then you may have TB. It is important to get a test done immediately.

Chronic chest pain

Since TB is a lung infection, you may experience chest pain that may be localized or start spreading. If you have a painful sensation every time you breathe, then you should get an AFB test done.

Strong fever

Fever is another critical indication that you may be dealing with an infection. If you have a strong fever and you are bed bound for several days, then you should get tested.



Blood while coughing

The presence of blood when coughing is an alarming symptom that shouldn't be ignored. You should get an acid fast bacilli AFB test done immediately.

Chronic fatigue

The symptom of chronic fatigue is also critical to track, especially if you have been experiencing other symptoms as well.


Sweating at night

Night sweats are a common symptom of a lung infection, and you may also experience other symptoms such as sudden pain.

Sudden weight loss

Weight loss that is sudden and unexplainable can be attributed to TB or other infections.

Loss of appetite

A complete or significant loss of appetite is a key sign of TB.

Long-term body pain

A sensation of chronic pain throughout the body is another important sign that your body may be dealing with an infection.



Benefits of timely detection of tuberculosis

There are several benefits of timely detection of TB, which is why it is important to get tested immediately. When it comes to the AFB, this test is designed such as that the presence of the infection can be detected immediately.

Lower risk of escalation

There is a significant reduction of risk of escalation when TB is detected in a timely manner.


Better chance of recovery

Your recovery and treatment effectiveness is significantly greater when you have a timely diagnosis.

Low risk of spreading

You also lower your risk of endangering your loved ones with TB.

Better understanding of symptoms

You can rule out other conditions when you have a clearer understanding of your symptoms.


* Medical Disclaimer - The following information is for educational purposes only. No information provided on this website, including text, graphic, and images, are intended as substitutes for professional medical advice. Please consult with your doctor about specific medical advice pertaining to your condition(s).

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