What is it?

Sputum (say "SPYOO-tum") is a thick fluid, or mucus, made in the lungs and in the airways leading to the lungs. A sputum culture tests a sample of sputum to see if it contains germs. The sputum is placed in a container with substances that help germs grow.

Why is this test done?

A sputum culture is done to find and identify bacteria that are causing a lung infection such as pneumonia or tuberculosis. The culture can also find the best antibiotic to treat the infection. And it can check to see how treatment is working.

How do you prepare for the test?

Don't use mouthwash before this test.

How is the test done?

• You rinse your mouth with water, take a deep breath, and then cough deeply to produce a sample of sputum.
• The health professional collecting the sample may tap on your chest to help loosen the sputum in your lungs before you cough.
• If you still have trouble coughing up a sample, you may be asked to inhale an aerosol mist to help you cough.

How long does the test take?

• The test will take a few minutes.

What happens after the test?

• You will probably be able to go home right away.
• You can go back to your usual activities right away.
• Your throat may feel sore if you had bronchoscopy or if the sputum was collected using a nasotracheal catheter.