SPUTUM EXAMINATION, AFB (Includes ZN, AURAMINE)

The Sputum AFB test is a very basic but vital test to determine if a person has Mycobacterium tuberculosis (the pathogen responsible for Tuberculosis (TB)). Testing for tuberculosis with sputum AFB is conducted by visualizing mucus (sputum) that is produced in the lungs and coughed out and subsequently looking under the microscope using specific stains. The test is a primary source of establishing whether you have an active TB infection.

Process: 

• Collect the sputum sample through a deep cough into a soaking sterile container. 
• Sputum samples will be smeared on a glass slide following the staining of the sputum using the Ziehl-Neelsen or Auramine techniques. 
• Once there is a visual staining of the sputum sample, the glass slide will be examined under a microscope for the presence of acid-fast Bacilli (AFB) that appear bright pink or fluorescent in the shape of rods. 

 When to get tested 

Those who have one or more of the following symptoms such as persistent cough lasting longer than the previous week, Chest pain, Coughing blood or fever and weight loss.

It is also worth being tested if you have been in close contact with an individual who has been diagnosed with Tuberculosis.

Sample Type

You must provide a fresh sputum sample that has been collected early in the morning, and expectorated making sure that the mucus comes from the deepest part of the lungs.

Test Preparation

Make sure to brush your teeth and rinse your mouth out before collection. Don't eat, drink, or smoke immediately before the test. 

Understanding Your Results

A positive result shows that tuberculosis (TB) bacteria are present and the person is infected. Treatment will be necessary. A negative result does not rule out TB altogether; if the person is symptomatic, or if there remains a clinical suspicion, more tests may be indicated.