Sputum is matter that is coughed up from the respiratory tract, such as
mucus or
phlegm, mixed with
saliva and then
expectorated from the mouth.A sputum sample is the name given to the
mucus that is coughed up from the lower airways. It is usually used for microbiological investigations of respiratory infections.The best sputum samples contain very little
saliva, as this contaminates the sample with oral
bacteria.
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