We developed an algorithm that can be used to make an initial choice of a probe (either Mycobacterium tuberculosis complex [MTB] or M. avium complex [MAC]) for use in testing respiratory specimens.
When AMPLICOR MTB results were compared with resolved results, i.e., a specimen grew M. tuberculosis or was obtained from a patient with a clinical diagnosis of tuberculosis, the sensitivity, specificity, positive predictive value, and negative predictive value for the AMPLICOR MTB test were 66.7, 99.6, 91.7, and 97.7%, respectively.
These results confirm the reliability of the AMPLICOR MTB assay for direct detection of M. tuberculosis in AFB smear-positive sputum specimens and suggest a potential role in evaluating AFB smear-negative sputum specimens.
A ligase chain reaction (LCR) DNA amplification method for the molecular diagnosis of Mycobacterium tuberculosis (Abbott LCx MTB) was evaluated in comparison with solid and liquid phase culture on 622 selected samples collected in two large Italian hospitals, of which 310 obtained from HIV-1 positive patients and 312 from HIV-negative individuals.
A positive LCx-MTB result in a smear negative specimen was 100% predictive that at least one of the case patients' specimens would yield M. tuberculosis.
The aim of this study was to compare the results of a commercial assay based on the ligase chain reaction [(LCR) LCx Probe System MTB; Abbott, USA] with those of culture in liquid medium (Septi-Chek AFB; Becton-Dickinson, USA) and culture on the egg-based Löwenstein-Jensen solid medium for the direct detection of Mycobacterium tuberculosis complex in nonrespiratory specimens.
The performance was evaluated of a fluorescence in situ hybridisation assay using peptide nucleic acid probes (Dako Probe MTB Culture Confirmation Test; Dako, Denmark) for identification of Mycobacterium tuberculosis complex (MTC) organisms and differentiation between tuberculous and non-tuberculous mycobacteria (NTM) in material taken directly from Bactec 12B (Becton Dickinson, USA) and MB/BacT (Organon Teknika, USA) bottles.
A new fluorescence in situ hybridization assay based on peptide nucleic acid probes (MTB and NTM probes targeting tuberculous and nontuberculous species, respectively) for the identification of Mycobacterium tuberculosis complex and differentiation between tuberculous and nontuberculous mycobacteria (NTM) was evaluated using Lowenstein-Jensen (LJ) solid cultures from 100 consecutive sputum samples and 50 acid-fast bacillus (AFB)-positive sputum samples as well as Mycobacteria Growth Indicator Tube (MGIT) liquid cultures from 80 AFB-positive sputum samples.
Performance of an IS6110-based PCR assay and the COBAS AMPLICOR MTB PCR system for detection of Mycobacterium tuberculosis complex DNA in human lymph node samples.
These results indicate that the Cobas Amplicor MTB test enables detection of tuberculosis in respiratory specimens, but does not perform well enough in non-respiratory specimens.
The BDProbeTec MTB assay for direct detection of Mycobacterium tuberculosis was evaluated in comparison with the AMTD-II assay on 94 samples from different patients with clinical suspicion of tuberculosis.
Among the 48 nonrespiratory specimens, the RAPID BAP-MTB assay was positive in one biopsy sample from a patient with lumbar tuberculous spondylitis and one pus sample from a patient with tuberculous cervical lymphadenopathy.
Difficulty in obtaining large quantities of Mycobacterium tuberculosis (MTB) proteins remains a major obstacle in the development of subunit vaccines and diagnostic reagents for tuberculosis.
These results demonstrate that the use of in vitro models of MTB-intracellular infection to select MTB gene products for further in silico and in vitro assessment of their immunogenicity have the potential to identify novel antigens amenable to the design of new tools for diagnosis and monitoring of tuberculosis.
Mycobacteria, including most of all MTB (Mycobacterium tuberculosis), cause pathogenic infections in humans and, during the infectious process, are exposed to a range of environmental insults, including the host's immune response.
The Mycobacterium tuberculosis specific LAMP assay ('MTB LAMP') showed sensitivity and specificity, of 44.7% and 94.4% respectively in a 60 min format, 85.7% and 93.9% respectively in a 90 min format and 91.7%, and 90.9% respectively in a 120 min format.
We determined the performance of the MTB/RIF assay for rapid diagnosis of tuberculosis and detection of rifampin resistance in smear-positive and smear-negative pulmonary and extrapulmonary specimens obtained from possible tuberculosis patients.
Of these, three strains were found to be the most prevalent: M. tuberculosis T1 (MTB T1; 38.9%), M. africanum F2 (MAF2; 26.2%) and M. tuberculosis Latin American and Mediterranean 10 (MTB LAM 10; 10.3%).