Pooja SAXENA, Ashish K. ASTHANA, Molly MADAN

Comparison of microscopy and PCR in detection of Mycobacterium tuberculosis

Giriş: Tüberküloz dünyanın her yerinde hala önemli bir mortalite ve morbidite nedenidir. TB’nin erken tanınması daha iyi tedavi sonuçları ve MDR-TB’nin daha az bulaşmasını sağlar. Bu çalışmanın amacı flöresan boyama, Ziehl-Neelson mikroskobi ve PCR metotlarının duyarlılığını araştırmaktır.Yöntemler: Klinik olarak akciğer tüberküloz şüphesi olan vakalardan 50 örnek toplandı ve mikobakteriler için floresan ve ZN boyalarla değerlendirildi. Boyama metotları ile negatif olan örnekler M. tuberculosis complex IS6110 primeri kullanılarak PCR metodu ile değerlendirildi. Bulgular: Elli örnekten 33’ü (% 66,0) floresan ile ve 23’ü (% 46,0) ZN ile pozitifti. Mikroskobik olarak negative olan bütün örnekler (n=17) PCR ile çalışıldı ve sadece yedi örnek (% 41,1) pozitif bulundu. Sonuç: PCR en iyi metot olarak görülmektedir ancak ciddi altyapı yatırımı gerektirmektedir

Anahtar Kelimeler:

Mycobacterium tuberculosis, PCR, floresan, Ziehl Neelsen, mikroskopi, tespit

Comparison of microscopy and PCR in detection of Mycobacterium tuberculosis

Objective: Tuberculosis (TB) one of the most important major causes of mortality and morbidity around the world. Early detection of TB affords to prevent transmission of TB and better treatment options. The aim of this study is to evaluate sensitivity of fluorescent, Ziehl Neelsen microscopy and Polymerase Chain Reaction (PCR) method. Methods: Fifty samples of clinically suspected cases of pulmonary tuberculosis were collected and processed for Mycobacteria by Fluorescent and ZN staining. Negative samples by staining methods were processed by PCR method using primer IS6110 of M. tuberculosis complex. Results: 33/50 (66.0%) samples were positive by Fluorescent and 23/50 (46%) were positive by ZN method. All microscopically negative samples (n=17) were processed to PCR and only seven of samples (41.1%) showed positive results. Conclusion: We concluded that PCR is best but it required lot of investment.

Keywords:

Mycobacterium tuberculosis,

PDF

___

Park K. Tuberculosis, In: Park’s Textbook of Preventive and Social Medicine, 15th edition. Banarasidas Bhanot Publish- ers, 1997, 138-151.
WHO Global Tuberculosis Report-2012. www.who.int/iris/bitstr eam/10665/75938/1/9789241564502_eng.pdf
Sandhu G K. Tuberculosis: Current Situation, Challenges and Overview of its Control Programs in India J Global Infect Dis 2011;3(2):143-150.
Sachdeva KS, Kumar A, Dewan P, et al. New version of Re- vised National Tuberculosis Control Program (RNTCP): Uni- versal Access-“Reaching the Unreached”. Ind J Med Res 2012;135:690-694.
Saroj H, Nita P, Malhotra B, et al. Comparison of Zeihl Neelsen and Auramine-O-Staining Methods on Direct and Concen- tration Smears in Clinical Specimens. Ind J Tuberculosis 2011;58(2):51-53.
Kocagoz T, Maz E, Ozkara E, et al. Detection of Mycobacte- rium tuberculosis in sputum samples by Polymerase Chain Reaction using a simplified procedure. J Clin Microbiol 1993;31(6):1435-1438.
Somoskovi A, Hotaling JE, Lessons from a proficiency testing event for acid fast microscopy. Chest 2001;120(1):250-257.
Kansal R, Agarwal C, Madan M, Asthana AK. Rapid diagnosis of extrapulmonary tuberculosis by nested polymerase chain reaction (nPCR) based on IS 6110 insertion sequence of My- cobacterium tuberculosis. Asian J Microbiol, Biotech Env Sc 2013;15(3):517-520
Hendry C, Dionne K, Hedgepeth A, et al. Evaluation of a Rapid Fluorescent Staining Method for Detection of Mycobacteria in Clinical Specimens. J Clin Microbiol 2009; 47(4):1206- 1208.