Test Overview
A sputum culture is
a test to detect and identify bacteria or
(plural of fungus) that are infecting the lungs
or breathing passages. Sputum is a thick fluid produced in the lungs and in the
airways leading to the lungs. A sample of sputum is placed in a container with
substances that promote the growth of bacteria or fungi. If no bacteria or
fungi grow, the culture is negative. If organisms that can cause infection
(pathogenic organisms) grow, the culture is positive. The type of bacterium or
fungus will be identified with a microscope or by chemical tests.
If bacteria or fungi that can cause infection grow in the culture, other
tests may be done to determine which antibiotic will be most effective in
treating the infection. This is called susceptibility or
sensitivity testing.
This test is done on
a sample of sputum that is usually collected by coughing. For people who can't
cough deeply enough to produce a sample, they can breathe in a mist solution to
help them cough.