Routine sputum culture is a test of secretions from the lungs and bronchi (tubes that carry air to the lung) to look for bacteria that cause infection.
How the test is performed:
You will cough deeply and spit any sputum into a sterile cup. The sputum is then taken to the laboratory. There, it is placed in a special substance (medium) under conditions that allow the bacteria or fungi to grow.
How to prepare for the test:
Drinking a lot of water and other fluids the night before the test may help to get the sample.
How the test will feel:
You will need to cough. Sometimes the health care provider will tap on the chest to loosen deep sputum. There may be a steam-like mist to inhale to help you cough up the sample.
Why the test is performed:
The culture is done on the sputum to help identify the bacteria that are causing an infection in the lungs or airways (bronchi).
No presence of disease-causing organisms in the sputum is normal.
What abnormal results mean:
Abnormal results will be reported as a positive culture. That means that there is a disease-producing organism found that may help diagnose:
Other conditions under which the test may be performed:
What the risks are:
There are no risks with this method of obtaining a sample.
Sometimes a gram stain or AFB stain of the sputum done at the same time can help make the diagnosis.