Home About TB TB History Human Impact Timeline People Profiles Sanatorium Age Preventing TB Finding TB Treating TB International TB Today Index

  Diagnosis of TB

 Laboratory Tests

The basic lab tests performed on the sputum sample are the same today as they were back in the days of the sanatoriums. Once a sputum sample is obtained from the patient, at least three procedures are performed. First a smear is made and stained in such a manner that tubercle bacilli may be identified by examination under the microscope. Secondly, a portion of the gastric washings is treated to destroy any secondary infection, and the resulting sediment is divided in two portions, one to be plated on culture media, which is especially prepared for the growth of tubercle bacilli, and the other half is used for animal inoculation. Tubercle bacilli are very slow growing organisms so we must wait a period of from three to six weeks for the results of the culture and the animal inoculation.

 Skin Test
 Mass Surveys
 Sputum Test
 Gastric Washing
 Laboratory Tests

Electron-microscope image of a Mycobacteria tuberculosis bacterium (Image used with permission of Yvonne Kress, Albert Einstein College of Medicine, and Kathleen McDonough, Ph.D., Wadsworth Center - New York State Department of Health).