Sputum DFA (direct fluorescent antibody)

How the test is performed:

A sputum sample is obtained by coughing into a specimen container. In the laboratory, antibodies that have been stained by a fluorescent dye are added to the sample. The "flagged" antibodies will form a complex with specific antigens (in this case, the microorganism against which they were formed). The specific microorganism (antigen) is indirectly identified by the presence of a reaction against a known, flagged antibody.

How to prepare for the test:

Obtain a coughed sputum specimen. If there is not a productive cough, a respiratory treatment may produce a sample.

How the test will feel:

There is no discomfort.

Why the test is performed:

This test may be performed when certain types of pulmonary infections or pneumonias are suspected.