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Sputum cytology examines a sample of sputum (mucus) under a microscope to determine whether abnormal cells are present. Sputum is not the same as saliva. Sputum is produced in the lungs and in the airways leading to the lungs. Sputum has some normal lung cells in it.
Sputum cytology may be done to help detect certain non-cancerous lung conditions. It may also be done when lung cancer is suspected.
A sputum sample may be collected:
Sputum cytology is done to find:
No special preparation is required if the sputum sample is to be collected at home or in your doctor's office.
Before you have bronchoscopy to collect a sputum sample, tell your doctor if you:
If you have a bronchoscopy, you will be asked to sign a consent form that says you understand the risks of the test and agree to have it done.
Talk to your doctor about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form .
Your doctor will tell you how soon before the procedure to stop eating and drinking. Follow the instructions exactly about when to stop eating and drinking, or your procedure may be cancelled. If your doctor has instructed you to take your medicines on the day of your procedure, please do so using only a sip of water.
Arrange to have someone drive you home after the procedure.
Three sputum samples are usually collected over 3 days. Your doctor will give you a container to collect the sputum. This container may have a small amount of liquid (called fixative) in it. The fixative helps preserve the sample. Do not drink this liquid.
For best results, collect the sample in the morning right after waking up. Follow these steps:
Carefully follow your doctor's instructions about where to deliver the sample. You may be instructed to take the sample to the doctor's office or to a laboratory. Deliver the sample soon after you obtain it. You may be instructed to refrigerate the sample if you are not able to deliver it immediately.
During bronchoscopy, a thin, lighted instrument (bronchoscope) is inserted through the nose or mouth into the throat and then into the airways leading to the lungs. To learn more about how the procedure is done, see the topic Bronchoscopy.
If you have discomfort when taking a deep breath or coughing, getting a sputum sample may be uncomfortable.
You may be able to feel pressure in your airway as the bronchoscope is moved from place to place. You may gag or cough. To learn more about how the procedure feels, see the topic Bronchoscopy.
There is no risk linked with collecting a sputum sample at home or at your doctor's office.
Bronchoscopy is generally a safe procedure. Although complications are rare, you should discuss the risks in your particular case with your doctor. Complications that may occur include:
Sputum cytology examines a sample of sputum (mucus) under a microscope to determine whether abnormal cells are present. It may take several days to receive results from a sputum cytology.
Normal lung cells are present in the sputum sample.
Abnormal cells are present in the sputum sample. Abnormal cells may mean lung conditions such as pneumonia, inflammation, the buildup of asbestos fibres in the lungs (asbestosis), or lung cancer.
Reasons you may not be able to have the test or why the results may not be helpful include a sample that is too small; is dried out; contains only saliva; or is from nasal secretions, not your airway.
Other Works ConsultedChernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby.
Current as of: February 24, 2020
Author: Healthwise StaffMedical Review: Adam Husney MD - Family MedicineAnne C. Poinier MD - Internal MedicineE. Gregory Thompson MD - Internal MedicineRobert L. Cowie MB, FCP(SA), MD, MSc, MFOM - PulmonologyElizabeth T. Russo MD - Internal Medicine
Current as of: February 24, 2020
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & Anne C. Poinier MD - Internal Medicine & E. Gregory Thompson MD - Internal Medicine & Robert L. Cowie MB, FCP(SA), MD, MSc, MFOM - Pulmonology & Elizabeth T. Russo MD - Internal Medicine
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