I am suffering from pulmonary TB. My doctor suggested a sputum test. I have a container for collecting sputum sample. Two days ago when I tired to collect a sample, only saliva came out in the container, but there was no sputum. Today while coughing I felt sputum in my mouth and I spitted in the same container. Now my concern is, will the sputum sample be useful even when it has got mixed with the saliva collected 2 days back?