African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12487

Full Length Research Paper

Evaluation of loop mediated isothermal amplification for diagnosis of Mycobacterium tuberculosis complex in clinical samples

Leila Kohan1*, Mohammad Hassan Shahhosseiny2, Mohammad Reza Razavi3,Kazem Parivar1, Elham Moslemi4 and Jim Werngren5        
1Islamic Azad University, Science and research branch, Department of Biology, Tehran, Iran. 2Islamic Azad University, Qods unit, Department of Microbiology, Tehran, Iran. 3Pasteur Institute of Iran, Department of Mycobacteriology, Tehran, Iran. 4Islamic Azad University, Qiamdasht branch, Department of Biology,Tehran ,Iran.  5Swedish Institute for Infectious Disease Control, Department of bacteriology, Solna, Sweden.
Email: [email protected]

  •  Accepted: 11 April 2011
  •  Published: 13 June 2011

Abstract

Tuberculosis (TB) remains an important global public health problem. The lack of rapid and accurate diagnostic testing is an important impediment to global tuberculosis control. Loop mediated isothermal amplification (LAMP) is a rapid method for nucleic acid amplification. In this study, we assessed the performance of an in-house LAMP assay for the detection of tuberculosis. Six oligonucleotide primers specific for Mycobacterium tuberculosis complex were designed corresponding to IS6110 gene sequence. Optimization of LAMP reaction was performed. A total of 133 clinical sputum samples and 80 bacterial cultures were studied by LAMP method. Sensitivity of this assay for detection of genomic DNA was 5 fg. This assay successfully detected M. tuberculosis complex not only in the bacterial cultures but also in the clinical sputum samples from patients with TB. The sensitivity of LAMP in culture-positive samples was 100% (60/60) and the specificity in culture-negative samples was 95.9% (70/73, 95% confidence interval 91.3 to 98.7%). Thus, LAMP is a rapid, highly sensitive and specific DNA amplification technique for early diagnosis of TB.

 

Key words: Loop mediated isothermal amplification (LAMP), polymerase chain reaction (PCR), IS6110 gene, Mycobacterium tuberculosis, diagnosis.