AMPLIFICATION OF MYCOBACTERIUM-TUBERCULOSIS FROM PERIPHERAL-BLOOD

To determine the value of the PCR assay of lymphomonocytic blood cells for the diagnosis of pulmonary tuberculosis, we compared, in a prospe ctive study, PCR results with results of conventional diagnostic metho ds of Mycobacterium tuberculosis detection. Clinical investigators who were unaware of the PCR data classified 162 immunocompetent patients, who had been hospitalized because of suspected pulmonary tuberculosis , in accordance with the recommendations of the American Thoracic Soci ety (ATS), By testing blood samples from these patients for mycobacter ial DNA with three different PCR systems, we were able to demonstrate that nonquantitative PCR of peripheral blood leukocytes is of little v alue for the specific diagnosis of pulmonary tuberculosis, However, se miquantitative PCR assays might have some significance since we found an increasing level of mycobacterial DNA copies in blood from patients classified in ATS groups 2 to 5.