Comparison of microscopy and PCR in detection of Mycobacterium tuberculosis

Abstract

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

Comparison of microscopy and PCR in detection of Mycobacterium tuberculosis

Öz

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

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