Diagnostic Significance of Polymerase Chain Reaction as Compare to Culture and Direct Microscopy in Cases of Pulmonary Tuberculosis
Background: Tuberculosis (TB) is presently an important health problem worldwide. Situation has changed in recent years due to AIDS pandemic. Hence, it urges the need to introduce specific methods for rapid diagnosis to avoid unnecessary or improper treatment. At present, sputum microscopy is the sole rapid diagnostic method available. Sputum culture may require more than 2 weeks to confirm diagnosis. Hence, detection of Mycobacterium tuberculosis by enzymatic amplification (polymerase chain reaction [PCR]) has been found useful in diagnosis of pulmonary TB.
Materials and Methods: The present study includes 45 sputum samples of patients presenting to TB chest OPD with productive cough for more than 2 weeks. Diagnostic tests are applied on sputum samples - direct microscopy by Ziehl–Neelsen staining, culture by modified Petroff’s method, and PCR by commercially available kit (Bio basic INC).
Results: Of 45 sputum sample, TB was confirmed by culture in 19 patients, acid-fast bacilli detected in 18 of 19 patients, and all of these patients were positive for PCR.
Conclusion: PCR is extremely helpful in detecting Mycobacterium TB in sputum sample as compare to culture and direct microscopy.
2. Narain JP, Raviglione MC, Kochi A. HIV-associated tuberculosis in
developing countries: Epidemiology and strategies for prevention. Tubercle
3. Boyd JC, Marr JJ. Decreasing reliability of acid–fast smear techniques for
detection of tuberculosis. Ann Intern Med 1995;82:489-92.
4. Kim TC, Blackman RS, Heatwole KM, Kim T, Rochester DF. Acidfast
bacilli in sputum smears of patients with pulmonary tuberculosis.
Prevalence and significance of negative smears pretreatment and positive
smears post-treatment. Am Rev Respir Dis 1984;129:264-8.
5. Menzies D. Issue in the management of contacts of patients with active
pulmonary tuberculosis. Can J Public Health 1997;88:197-201.
6. Behr MA, Warren SA, Salamon H, Hopewell PC, Ponce de Leon A,
Daley CL, et al. Transmission of Mycobacterium tuberculosis from patients
smear-negative for acid-fast bacilli. Lancet 1999;353:444-9.
7. Toman K. Tuberculosis–case-finding and chemotherapy: Questions and
answers. Geneva: World Health Organization; 1979.
8. Morgan MA, Horstmeier CD, Deyoung DR, Roberts GD. Comparison of
a radiometric method (BACTEC) and convectional media for recovery
of mycobacteria from smear-negative specimens. J Clin Microbiol
9. Isenberg HD, Damato RF, Heifets L, Murray PR, Scardamaglia M,
Jacobs MC, et al. Collaborative feasibility study of a biphasic system
(Roche Septi-Check AFB) for rapid detection and isolation of mycobacteria.
J Clin Microbiol 1991;29:1719-22.
10. Pao CC, Yen B, You J, Maa JS, Fiss EH, Chang CH. Detection and
identification of Mycobacterium tuberculosis by DNA amplification. J Clin
11. de Wit D, Maartens G, Steyn L. A comparative study of the polymerase
chain reaction and conventional procedures for the diagnosis of tuberculous
pleural effusion. Tuber Lung Dis 1992;73:262-7.
12. Shankar P, Manjunath N, Mohan KK, Prasad K, Behari M., Shrinivas, et al.
Rapid diagnosis of tuberculosis meningitis by polymerase chain reaction.
13. Hance AJ, Grandchamp B, Lévy-Frébault V, Lecossier D, Rauzier J,
Bocart D, et al. Detection and identification of mycobacteria by
amplification of mycobacterial DNA. Mol Microbiol 1989;3:843-9.
14. Brisson-Noël A, Gicquel B, Lecossier D, Lévy-Frébault V, Nassif X,
Hance AJ, et al. Rapid diagnosis of tuberculosis by amplification of
mycobacterial DNA in clinical samples. Lancet 1989;2:1069-71.
15. Shankar P, Manjunath N, Lakshmi R, Aditi B, Seth P, Shriniwas, et al.
Identification of Mycobacterium tuberculosis by polymerase chain reaction.
16. Manjunath N, Shankar P, Rajan L, Bhargava A, Saluja S, Shriniwas, et al.
Evaluation of a polymerase chain reaction for the diagnosis of tuberculosis.
17. Patel RJ, Fries JW, Piessens WF, Wirth DF. Sequence analysis and
amplification by polymerase chain reaction of a cloned DNA fragment
for identification of Mycobacterum tuberculosis. J Clin Microbiol
18. Sjdbring U, Mechlenburg M, Andersen AB, Miörner H. Polymerase chain
reaction for detection of Mycobacterium tuberculosis. J Clin Microbiol
19. Soini H, Skurnik M, Liipo K, Tala E, Viljanen MK. Detection and
identification of mycobacteria by amplification of a segment of the gene
coding for the 32- kilodalton protein. J Clin Microbiol 1992;30:2025-8.
20. Cousins DV, Wilton SD, Francis BR, Gow BL. Use of polymerase chain
reaction for rapid diagnosis of tuberculosis. J Clin Microbiol 1992;30:255‑8.
21. Del Portillo P, Murillo LA, Patarroyo ME. Amplification of a speciesspecific
DNA fragment of Mycobacterium tuberculosis and its possible use
in diagnosis. J Clin Microbiol 1991;29:2163-8.
22. Altamirano M, Kelly MT, Wong A, Bessuille ET, Black WA, Smith JA,
et al. Characterization of a DNA probe for detection of Mycobacterium
tuberculosis complex in clinical samples by polymerase chain reaction.
J Clin Microbiol 1992;30:2173-6.
23. Thierry D, Brisson-Noël A, Vincent-Lévy-Frébault V, Nguyen S,
Guesdon JL, Gicquel B, et al. Characterization of a Mycobacterium
tuberculosis insertion sequence, IS6110, and its application in diagnosis.
J Clin Microbiol 1990;28:2668-73.
24. Eisenach KD, Cave MD, Bates JH, Crawford JT. Polymerase chain reaction
amplification of a repetitive DNA sequence specific for Mycobacterium
tuberculosis. J Infect Dis 1990;161:977-81.
25. De Wit D, Steyn L, Shoemaker S, Sogin M. Direct detection of
Mycobacterium tuberculosis in clinical specimens by DNA amplification.
J Clin Microbiol 1990;28:2437-41.
26. Eisenach KD, Sifford MD, Cave MD, Bates JH, Crawford JT. Detection of
Mycobacterium tuberculosis in sputum samples using a polymerase chain
reaction. Am Rev Respir Dis 1991;144:1160-3.