BCG lymphadenopathy detected in a BCG-vaccinated infant (original) (raw)

Allele-specific PCR method based on pncA and oxyR sequences for distinguishing Mycobacterium bovis from Mycobacterium tuberculosis: intraspecific M. bovis pncA …

Journal of clinical …, 1998

An allele-specific amplification method based on two genetic polymorphisms to differentiate Mycobacterium tuberculosis from Mycobacterium bovis was tested. Based on the differences found at position 169 in the pncA genes from M. tuberculosis and M. bovis, a PCR system which was able to differentiate most of the 237 M. tuberculosis complex isolates tested in one of the two species was developed. All 121 M. tuberculosis strains showed the expected base (cytosine) at position 169. Most of the M. bovis isolates had a guanine at the cited position. Nevertheless, 18 of the 116 M. bovis isolates, all of them goat isolates, showed the pncA polymorphism specific to M. tuberculosis. These results suggest that goat M. bovis may be the nicotinamidase-missing link at the origin of the M. tuberculosis species. Based on the polymorphism found at position 285 in the oxyR gene, the same system was used to differentiate M. tuberculosis from M. bovis. In this case, DNAs from all 121 M. tuberculosis isolates had the expected base (guanine) at this position. In addition, all 116 M. bovis isolates, including those from goats, showed the identical polymorphism (adenine). The oxyR allele-specific amplification method can differentiate M. bovis from M. tuberculosis, is rapid (results can be obtained in less than 3 h), and is easy to perform.

A pncA polymorphism to differentiate between Mycobacterium bovis and Mycobacterium tuberculosis

Molecular and Cellular Probes, 2004

The pyrazinamidase gene coding for the enzyme that activates the bactericidal drug pyrazinamide contains a polymorphic site that is preserved in Mycobacterium bovis. We synthesized two sets of primers, one encompassing a 180 bp fragment, and the second spanning a 726 bp fragment including the full pncA gene. Following PCR of Mycobacterium tuberculosis and M. bovis samples, it is possible to discriminate by this polymorphism between these species by digestion with Eco065 I. Digestion of the 180 bp fragment results in two fragments of 101 and 79 bp, specific for M. tuberculosis. Alternatively, digestion of the 726 bp fragment yields three fragments of 452, 165 and 109 bp for M. tuberculosis, but only two fragments of 561 and 165 bp for M. bovis.

Differentiation between Mycobacterium tuberculosis and Mycobacterium bovis by a multiplex-polymerase chain reaction

Journal of Applied Bacteriology, 1996

PEREZ AND M. SEGOVIA. 1996. A multiplex-polymerase chain reaction (PCR) assay, based on one-step amplification and detection of three different mycobacterial genomic fragments, was designed for differentiation between Mycobacterium bovis and M.jtcobacterium tuberculosis. T h e oligonucleotide primers were chosen from the groEL gene, present in the genus Mycobacterium sp., from the IS61 10 insertion sequence, present in M.)tco. tuberculosis complex and from the mtp40 gene, identified as a specificspecies M.yco. tuberculosis genomic fragment. This amplification method allowed the detection of two fragments of 576 and 317 base pairs in Myco. bovis and three fragments of 576, 396 and 317 base pairs in M.yco. tuberculosis strains, including atypical strains of Myco. tuberculosis where the copy number of the IS61 10 element is low. The multiplex-PCR assay described may be a very useful tool for the rapid and specific differentiation of these related mycobacteria and easy to use in medical and veterinary microbiology laboratories. 78 80 81 MT-1 51 61 79 245 616 689 1218 8702 9220 10 12760 M.yobacreriirnt chelonae M,yco. renopi M.yco. boris BCG M,yco. boris BCG M,yco. tuberculosis M.yco. kunsasii M,yco. fiirtuitum Myco. bovis M,yco. aaium-introcellulare M.yco. tubrrcukosis M,yco. tuberculosis M,yco. tubercu1osi.v M y c v. tuberculosis Myco. tuberculosis M.yco. tuberculosis Myco. murinum

Evaluation of PCR pncA-restriction fragment length polymorphism and PCR amplification of genomic regions of difference for the identification of M. bovis strains in lymph nodes cultures

African Health Sciences, 2021

Background: A rapid accurate identification of Mycobacterium bovis is essential for surveillance purposes. Objectives: A PCR pncA-Restriction Fragment Length Polymorphism (RFLP) and a multiplex PCR based on the detection of 3 regions of difference (RD-PCR): RD9, RD4 and RD1 were evaluated for the identification of M. bovis in lymph nodes cultures, in Tunisia, during 2013-2015. Methods: Eighty-two M. tuberculosis complex strains were identified using the biochemical tests, GenoType MTBC assay, PCR pncA-RFLP and RD-PCR. Results: The PCR pncA-RFLP showed that 54 M. bovis strains, identified by GenoType MTBC, had a mutation at position 169 of pncA gene. Twenty-eight strains did not show any mutation at this position 27 M. tuberculosis isolates and one M. caprae. The PCR pncA-RFLP had a sensitivity of 100.0% (95%CI: 93.3 -100.0) and a specificity of 100.0% (95%CI: 87.9- 100.0) for identifying M. bovis. The RD-PCR showed that all M. bovis strains had the RD9 and RD4 deleted but presented ...

Multiplex-PCR for differentiation of Mycobacterium bovis from Mycobacterium tuberculosis complex

Brazilian Journal of Microbiology, 2014

A multiplex-polymerase chain reaction (PCR) assay based on one-step amplification and detection of two different mycobacterial genomic fragments was designed for differentiation of Mycobacterium bovis and Mycobacterium tuberculosis. The oligonucleotide primers were chosen from a 500-bp genomic fragment which is well conserved in M. bovis and the pncA gene (based on M. tuberculosis-specific nucleotide polymorphism, a cytosine residue at position 169), specific for M. tuberculosis. The multiplex-PCR allowed detection of a single product of 500 bp in M. bovis isolates while M. tuberculosis isolates generated a single product of 185 bp, with or without an additional product of 500 bp. None of the atypical mycobacterial isolates revealed any amplification products. The method was found to be highly specific and could detect as little as 20 pg of pure DNA. This multiplex-PCR assay, based on the 500-bp fragment and the pncA gene, may be very useful for the rapid and specific differentiation of these two closely related mycobacteria and easy to use in medical and veterinary microbiological laboratories.

Genotyping did not evidence any contribution of Mycobacterium bovis to human tuberculosis in Brazil

Tuberculosis, 2011

The contribution of Mycobacterium bovis to the global burden of tuberculosis (TB) in man is likely to be underestimated due to its dysgonic growth characteristics and because of the absence of pyruvate in most used media is disadvantageous for its primary isolation. In Brazil Mycobacterium culture, identification and susceptibility tests are performed only in TB reference centers, usually for selected cases. Moreover, solid, egg-based, glycerol-containing (without pyruvate supplementation) Löwenstein-Jensen (L-J) or Ogawa media are routinely used, unfavouring M. bovis isolation. To determine the importance of M. bovis as a public health threat in Brazil we investigated 3046 suspected TB patients inoculating their clinical samples onto routine L-J and L-J pyruvate enriched media. A total of 1796 specimens were culture positive for Mycobacterium spp. and 702 TB cases were confirmed. Surprisingly we did not detect one single case of M. bovis in the resulting collection of 1674 isolates recovered from M. bovis favourable medium analyzed by conventional and molecular speciation methods. Also, bacillary DNA present on 454 sputum smears from 223 TB patients were OxyR genotyped and none was recognized as M. bovis. Our data indicate that M. bovis importance on the burden of human TB in Brazil is marginal.

A multiplex-PCR for the differentiation of Mycobacterium bovis and Mycobacterium tuberculosis

FEMS Microbiology Letters, 2002

A multiplex-polymerase chain reaction (PCR) assay based on one-step amplification and detection of two different mycobacterial genomic fragments was designed for differentiation of Mycobacterium bovis and Mycobacterium tuberculosis. The oligonucleotide primers were chosen from a 500-bp genomic fragment which is well conserved in M. bovis and the pncA gene (based on M. tuberculosis-specific nucleotide polymorphism, a cytosine residue at position 169), specific for M. tuberculosis. The multiplex-PCR allowed detection of a single product of 500 bp in M. bovis isolates while M. tuberculosis isolates generated a single product of 185 bp, with or without an additional product of 500 bp. None of the atypical mycobacterial isolates revealed any amplification products. The method was found to be highly specific and could detect as little as 20 pg of pure DNA. This multiplex-PCR assay, based on the 500-bp fragment and the pncA gene, may be very useful for the rapid and specific differentiation of these two closely related mycobacteria and easy to use in medical and veterinary microbiological laboratories.

Identification of Mycobacterium tuberculosis Antigens of High Serodiagnostic Value

2010

Background: Species identification of isolates belonging to the Mycobacterium tuberculosis complex (MTC) seems to be important for the appropriate treatment of patients, since M. bovis is naturally resistant to a first line anti-tuberculosis (TB) drug, pyrazinamide, while most of the other MTC members are susceptible to this antimicrobial agent. A simple and low-cost differentiation method was needed in higher TB burden countries, such as Bangladesh, where the prevalence of M. bovis among people or cattle has not been investigated.