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    Sputum Culture

    How It Is Done continued...

    If you wear dentures, you will need to take them out before you collect your sputum sample. Then rinse your mouth with water. Next, take a deep breath and cough deeply to get a sample of sputum. The person taking the sample may tap on your chest. This tapping helps 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.


    Some people may need bronchoscopy to collect a sputum sample. A thin, lighted tube (bronchoscope) is put through your mouth or nose into the airways leading to your lungs. You will get medicine that numbs your throat and nose so you do not feel pain from the bronchoscope. You may also get a sedative to make you sleepy during the test. To collect the sample, a salt solution may be washed into the airway and then suctioned into a container. A small, thin brush may be used to collect a sample.


    Suction can also be used to collect a sputum sample. A soft, flexible tube (called a nasotracheal catheter) is put through the nose and down the throat. Suction is applied for up to 15 seconds to collect the sample. This method is often used for people who are very sick or unconscious.

    After a sample is collected

    The sputum sample will be placed in a container with a growth medium or culture medium. These are substances that help with the growth of bacteria or fungi. Bacteria usually need 2 to 3 days to grow. Fungus often takes a week or longer to grow. The organism that causes tuberculosis may take 6 weeks to grow. Any bacteria or fungi that grow will be found under a microscope or by chemical tests. Sensitivity testing, to find the best antibiotic to use, often takes 1 to 2 more days.

    How It Feels

    If you have some pain when you take a deep breath or when you cough, giving a sputum sample may be uncomfortable. If you need to inhale the aerosol mist to produce a sample, you will likely feel a strong urge to cough.

    WebMD Medical Reference from Healthwise

    Last Updated: May 22, 2015
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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