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.
Alternative Names:
Sputum culture
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).
Normal Values:
In a normal sputum sample there will be no disease-causing organisms present.
What abnormal results mean:
If the sputum sample is abnormal, the results are called "positive." Identifying disease-producing organisms may help diagnose:
There are no risks with this method of obtaining a sample.
Special considerations:
Sometimes a Gram stain or AFB stain of the sputum done at the same time can help make the diagnosis.
Review Date: 10/15/2009 Reviewed By: Daniel Levy, MD, Infectious Disease, Maryland Family Care, Lutherville, MD. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
