Detection of Mycobacterium tuberculosis from Peripheral Blood of Patients with Tuberculosis by Polymerase Chain Reaction

Sohn, Jang Wook; Cheong, Hee Jin; Woo, Heung Jeong; Kim, Woo Joo; Kim, Min Ja; Park, Seung Chul

Abstract

BACKGROUND
Conventional diagnostic methods of pulmonary tuberculosis, such as acid-fast bacilli staining and culture of sputum, have the disadvantages of low sensitivity and long incubation period, respectively. The diagnosis of extrapulmonary tuberculosis needs invasive procedures. We investigated the value of PCR-based detection of Mycobacterium tuberculosis from peripheral blood mononuclear cells for diagnosis of pulmonary or extrapulmonary tuberculosis.
METHODS
The peripheral blood mononuclear cells were collected from 23 patients with pulmonary tuber-culosis( n=10) and extrapulmonary tuberculosis(n=13), in-cluding miliary tuberculosis(n=5), and 10 healthy indi-viduals as negative controls. A pair of primers was used to produce a 314 bp amplification product from the insertion element IS6110, which is specific for M. tuberculosis. PCR products were detected by agarose gel electrophoresis and southern hybridization using a IS6110 specific oligoprobe.
RESULTS
Eight out of ten with pulmonary tuberculo-sis and 9 out of 13 patients with extrapulmonary tuber-culosis showed positive results, yielding 73.9%(17/23) positivity on PCR assay. All five patients with miliary tuberculosis were positive. None of the healthy indivi-duals showed positive results.
CONCLUSION
The PCR assay for M. tuberculosis from peripheral blood seems to be useful for diagnosis of tuberculosis, especially miliary tuberculosis. Further studies about the value of the PCR assay in monitoring treatment response are needed.