Title: Role of Real Time PCR in Detection of MTB, MDR and XDR TB Directly from Sputum Specimens of Clinical Suspects of PTB
Authors: Preety Choudhary, Dr T. S. K. Singh, Dr Luna Adhikari, Dr Parvati Nandy, Deepan Gautam
DOI: https://dx.doi.org/10.18535/jmscr/v5i11.147
Abstract
Background and Objectives: “Presently, Sikkim has emerged as the next big concern on India’s already riddled tuberculosis map with 11 per cent of the new tuberculosis cases in the State found to be multi-drug-resistant”; as reported in The Hindu; 14th July 2016.The study intended in verifying the role of real time PCR in the detection of Mycobacterium tuberculosis, diagnosis of multi drug resistant tuberculosis and extensively drug resistant tuberculosis directly in sputum samples of pulmonary tuberculosis.
Materials and Methods: The sputum samples were subjected to fluorescence staining and real time PCR. For the detection of MDR and XDR TB cases the genes targeted were rpoB- rifampicin resistance, katG and in hA- isoniazid resistance, gyrA-fluoroquinolone resistance, rrs, eia-10 and eia-37- resistance to injectable drugs.
Results: The study revealed 50(61%) sputum positive and 32 (39%) sputum negative cases. However, real time PCR diagnosed 64(78%) positive cases. Fourteen MDR TB and 1 XDR TB cases were diagnosed simultaneously, with maximum MDR TB cases belonging to 3+ AFB grading.
Interpretation and Conclusion: Real time PCR showed better sensitivity, specificity and an early means of detection of Mycobacterium tuberculosisas well as multi drug resistant tuberculosis and extensively drug resistant tuberculosis in the suspected samples.
Keywords: Real time PCR, Multi drug-resistant tuberculosis, Extensively drug-resistant tuberculosis, Fluorescence staining.
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